ASP.NET Core fails to load assemblies after migration from .NET 5 to 6.0.1

Question

Recently, I upgraded our ASP.NET Core Web API project from .NET 5 to .NET 6.0.1. It was initially developed in .NET 5, but since this version is EOL somewhere this year and .NET 6 is the new LTS version, an upgrade seemed necessary for continued development.

The projects upgraded just fine, with the expected NuGet package errors and incompatibility between projects in the solution here and there. These were all fixed by upgrading the packages and upgrading the entire solution to .NET 6.

However, when I try to run it on my localhost (both in debug and release), the API fails to launch. The debug output shows a tonne of "Loading module", followed by "Pdb file for assembly <insert_path_to_assembly>.dll was not found or failed to read". At first I thought it must mean missing dependencies or NuGet packages, but even assemblies like System.Private.CoreLib.dll and System.Runtime.dll fail to load.

Below is the debug output:

Loaded application domain 'DefaultDomain (id 1)'
Loaded Assembly 'System.Private.CoreLib.dll'
Loading module System.Private.CoreLib.dll in application domain 1:DefaultDomain
Pdb file for assembly System.Private.CoreLib.dll was not found or failed to read
Loaded Assembly 'System.Runtime.dll'
Loading module System.Runtime.dll in application domain 1:clrhost
Pdb file for assembly System.Runtime.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Hosting.Abstractions.dll'
Loading module Microsoft.Extensions.Hosting.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Hosting.Abstractions.dll was not found or failed to read
Loaded Assembly 'netstandard.dll'
Loading module netstandard.dll in application domain 1:clrhost
Pdb file for assembly netstandard.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.DependencyInjection.Abstractions.dll'
Loading module Microsoft.Extensions.DependencyInjection.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.DependencyInjection.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.EntityFrameworkCore.dll'
Loading module Microsoft.EntityFrameworkCore.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.EntityFrameworkCore.dll was not found or failed to read
Loaded Assembly 'System.ComponentModel.dll'
Loading module System.ComponentModel.dll in application domain 1:clrhost
Pdb file for assembly System.ComponentModel.dll was not found or failed to read
Loaded Assembly 'Serilog.dll'
Loading module Serilog.dll in application domain 1:clrhost
Pdb file for assembly Serilog.dll was not found or failed to read
Loaded Assembly 'Microsoft.EntityFrameworkCore.Relational.dll'
Loading module Microsoft.EntityFrameworkCore.Relational.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.EntityFrameworkCore.Relational.dll was not found or failed to read
Loaded Assembly 'Serilog.Sinks.File.dll'
Loading module Serilog.Sinks.File.dll in application domain 1:clrhost
Pdb file for assembly Serilog.Sinks.File.dll was not found or failed to read
Loaded Assembly 'System.Text.Encoding.dll'
Loading module System.Text.Encoding.dll in application domain 1:clrhost
Pdb file for assembly System.Text.Encoding.dll was not found or failed to read
Loaded Assembly 'System.Console.dll'
Loading module System.Console.dll in application domain 1:clrhost
Pdb file for assembly System.Console.dll was not found or failed to read
Loaded Assembly 'System.Collections.dll'
Loading module System.Collections.dll in application domain 1:clrhost
Pdb file for assembly System.Collections.dll was not found or failed to read
Loaded Assembly 'System.Linq.dll'
Loading module System.Linq.dll in application domain 1:clrhost
Pdb file for assembly System.Linq.dll was not found or failed to read
Loaded Assembly 'System.IO.dll'
Loading module System.IO.dll in application domain 1:clrhost
Pdb file for assembly System.IO.dll was not found or failed to read
Loaded Assembly 'System.IO.FileSystem.dll'
Loading module System.IO.FileSystem.dll in application domain 1:clrhost
Pdb file for assembly System.IO.FileSystem.dll was not found or failed to read
Loaded Assembly 'System.Runtime.Extensions.dll'
Loading module System.Runtime.Extensions.dll in application domain 1:clrhost
Pdb file for assembly System.Runtime.Extensions.dll was not found or failed to read
Loaded Assembly 'System.IO.FileSystem.Primitives.dll'
Loading module System.IO.FileSystem.Primitives.dll in application domain 1:clrhost
Pdb file for assembly System.IO.FileSystem.Primitives.dll was not found or failed to read
Loaded Assembly 'System.Text.Encoding.Extensions.dll'
Loading module System.Text.Encoding.Extensions.dll in application domain 1:clrhost
Pdb file for assembly System.Text.Encoding.Extensions.dll was not found or failed to read
Loaded Assembly 'System.Private.Uri.dll'
Loading module System.Private.Uri.dll in application domain 1:clrhost
Pdb file for assembly System.Private.Uri.dll was not found or failed to read
Loaded Assembly 'System.Memory.dll'
Loading module System.Memory.dll in application domain 1:clrhost
Pdb file for assembly System.Memory.dll was not found or failed to read
Loaded Assembly 'System.Threading.dll'
Loading module System.Threading.dll in application domain 1:clrhost
Pdb file for assembly System.Threading.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Hosting.dll'
Loading module Microsoft.Extensions.Hosting.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Hosting.dll was not found or failed to read
Loaded Assembly 'Serilog.Extensions.Hosting.dll'
Loading module Serilog.Extensions.Hosting.dll in application domain 1:clrhost
Pdb file for assembly Serilog.Extensions.Hosting.dll was not found or failed to read
Loaded Assembly 'Serilog.Extensions.Logging.dll'
Loading module Serilog.Extensions.Logging.dll in application domain 1:clrhost
Pdb file for assembly Serilog.Extensions.Logging.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Hosting.Abstractions.dll'
Loading module Microsoft.AspNetCore.Hosting.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Hosting.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.dll'
Loading module Microsoft.AspNetCore.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.Abstractions.dll'
Loading module Microsoft.Extensions.Configuration.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.DependencyInjection.dll'
Loading module Microsoft.Extensions.DependencyInjection.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.DependencyInjection.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.dll'
Loading module Microsoft.Extensions.Logging.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Hosting.dll'
Loading module Microsoft.AspNetCore.Hosting.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Hosting.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.dll'
Loading module Microsoft.Extensions.Configuration.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.EnvironmentVariables.dll'
Loading module Microsoft.Extensions.Configuration.EnvironmentVariables.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.EnvironmentVariables.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Primitives.dll'
Loading module Microsoft.Extensions.Primitives.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Primitives.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.Kestrel.Core.dll'
Loading module Microsoft.AspNetCore.Server.Kestrel.Core.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.Kestrel.Core.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.Kestrel.dll'
Loading module Microsoft.AspNetCore.Server.Kestrel.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.Kestrel.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.Kestrel.Transport.Quic.dll'
Loading module Microsoft.AspNetCore.Server.Kestrel.Transport.Quic.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.Kestrel.Transport.Quic.dll was not found or failed to read
Loaded Assembly 'System.Net.Quic.dll'
Loading module System.Net.Quic.dll in application domain 1:clrhost
Pdb file for assembly System.Net.Quic.dll was not found or failed to read
Loaded Assembly 'System.Runtime.InteropServices.dll'
Loading module System.Runtime.InteropServices.dll in application domain 1:clrhost
Pdb file for assembly System.Runtime.InteropServices.dll was not found or failed to read
Loaded Assembly 'System.Diagnostics.Tracing.dll'
Loading module System.Diagnostics.Tracing.dll in application domain 1:clrhost
Pdb file for assembly System.Diagnostics.Tracing.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.IIS.dll'
Loading module Microsoft.AspNetCore.Server.IIS.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.IIS.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.IISIntegration.dll'
Loading module Microsoft.AspNetCore.Server.IISIntegration.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.IISIntegration.dll was not found or failed to read
Loaded Assembly 'System.Diagnostics.DiagnosticSource.dll'
Loading module System.Diagnostics.DiagnosticSource.dll in application domain 1:clrhost
Pdb file for assembly System.Diagnostics.DiagnosticSource.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Core.dll'
Loading module Microsoft.AspNetCore.Mvc.Core.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Core.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.FileProviders.Physical.dll'
Loading module Microsoft.Extensions.FileProviders.Physical.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.FileProviders.Physical.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.FileProviders.Abstractions.dll'
Loading module Microsoft.Extensions.FileProviders.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.FileProviders.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.FileExtensions.dll'
Loading module Microsoft.Extensions.Configuration.FileExtensions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.FileExtensions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.Binder.dll'
Loading module Microsoft.Extensions.Configuration.Binder.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.Binder.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.Json.dll'
Loading module Microsoft.Extensions.Configuration.Json.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.Json.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Configuration.UserSecrets.dll'
Loading module Microsoft.Extensions.Configuration.UserSecrets.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Configuration.UserSecrets.dll was not found or failed to read
Loaded Assembly 'System.IO.FileSystem.Watcher.dll'
Loading module System.IO.FileSystem.Watcher.dll in application domain 1:clrhost
Pdb file for assembly System.IO.FileSystem.Watcher.dll was not found or failed to read
Loaded Assembly 'System.ComponentModel.Primitives.dll'
Loading module System.ComponentModel.Primitives.dll in application domain 1:clrhost
Pdb file for assembly System.ComponentModel.Primitives.dll was not found or failed to read
Loaded Assembly 'System.Collections.Concurrent.dll'
Loading module System.Collections.Concurrent.dll in application domain 1:clrhost
Pdb file for assembly System.Collections.Concurrent.dll was not found or failed to read
Loaded Assembly 'System.Threading.Overlapped.dll'
Loading module System.Threading.Overlapped.dll in application domain 1:clrhost
Pdb file for assembly System.Threading.Overlapped.dll was not found or failed to read
Loaded Assembly 'Microsoft.Win32.Primitives.dll'
Loading module Microsoft.Win32.Primitives.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Win32.Primitives.dll was not found or failed to read
Loaded Assembly 'System.Text.Json.dll'
Loading module System.Text.Json.dll in application domain 1:clrhost
Pdb file for assembly System.Text.Json.dll was not found or failed to read
Loaded Assembly 'System.Numerics.Vectors.dll'
Loading module System.Numerics.Vectors.dll in application domain 1:clrhost
Pdb file for assembly System.Numerics.Vectors.dll was not found or failed to read
Loaded Assembly 'System.Runtime.CompilerServices.Unsafe.dll'
Loading module System.Runtime.CompilerServices.Unsafe.dll in application domain 1:clrhost
Pdb file for assembly System.Runtime.CompilerServices.Unsafe.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Options.dll'
Loading module Microsoft.Extensions.Options.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Options.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.Abstractions.dll'
Loading module Microsoft.Extensions.Logging.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.EventLog.dll'
Loading module Microsoft.Extensions.Logging.EventLog.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.EventLog.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.Configuration.dll'
Loading module Microsoft.Extensions.Logging.Configuration.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.Configuration.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Options.ConfigurationExtensions.dll'
Loading module Microsoft.Extensions.Options.ConfigurationExtensions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Options.ConfigurationExtensions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.Console.dll'
Loading module Microsoft.Extensions.Logging.Console.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.Console.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.Debug.dll'
Loading module Microsoft.Extensions.Logging.Debug.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.Debug.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Logging.EventSource.dll'
Loading module Microsoft.Extensions.Logging.EventSource.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Logging.EventSource.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Http.Abstractions.dll'
Loading module Microsoft.AspNetCore.Http.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Http.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Features.dll'
Loading module Microsoft.Extensions.Features.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Features.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Http.dll'
Loading module Microsoft.AspNetCore.Http.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Http.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Hosting.Server.Abstractions.dll'
Loading module Microsoft.AspNetCore.Hosting.Server.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Hosting.Server.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Connections.Abstractions.dll'
Loading module Microsoft.AspNetCore.Connections.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Connections.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.dll'
Loading module Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets.dll was not found or failed to read
Loaded Assembly 'System.Net.Primitives.dll'
Loading module System.Net.Primitives.dll in application domain 1:clrhost
Pdb file for assembly System.Net.Primitives.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.HostFiltering.dll'
Loading module Microsoft.AspNetCore.HostFiltering.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.HostFiltering.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.HttpOverrides.dll'
Loading module Microsoft.AspNetCore.HttpOverrides.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.HttpOverrides.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Routing.dll'
Loading module Microsoft.AspNetCore.Routing.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Routing.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Routing.Abstractions.dll'
Loading module Microsoft.AspNetCore.Routing.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Routing.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.ObjectPool.dll'
Loading module Microsoft.Extensions.ObjectPool.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.ObjectPool.dll was not found or failed to read
Loaded Assembly 'System.ObjectModel.dll'
Loading module System.ObjectModel.dll in application domain 1:clrhost
Pdb file for assembly System.ObjectModel.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.dll'
Loading module Microsoft.AspNetCore.Mvc.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Cors.dll'
Loading module Microsoft.AspNetCore.Cors.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Cors.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Caching.Memory.dll'
Loading module Microsoft.Extensions.Caching.Memory.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Caching.Memory.dll was not found or failed to read
Loaded Assembly 'AspNetCoreRateLimit.dll'
Loading module AspNetCoreRateLimit.dll in application domain 1:clrhost
Symbols for module AspNetCoreRateLimit.dll loaded
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Versioning.dll'
Loading module Microsoft.AspNetCore.Mvc.Versioning.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Versioning.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Versioning.ApiExplorer.dll'
Loading module Microsoft.AspNetCore.Mvc.Versioning.ApiExplorer.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Versioning.ApiExplorer.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Abstractions.dll'
Loading module Microsoft.AspNetCore.Mvc.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Abstractions.dll was not found or failed to read
Loaded Assembly 'Swashbuckle.AspNetCore.SwaggerUI.dll'
Loading module Swashbuckle.AspNetCore.SwaggerUI.dll in application domain 1:clrhost
Pdb file for assembly Swashbuckle.AspNetCore.SwaggerUI.dll was not found or failed to read
Loaded Assembly 'Swashbuckle.AspNetCore.SwaggerGen.dll'
Loading module Swashbuckle.AspNetCore.SwaggerGen.dll in application domain 1:clrhost
Pdb file for assembly Swashbuckle.AspNetCore.SwaggerGen.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authentication.dll'
Loading module Microsoft.AspNetCore.Authentication.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authentication.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authentication.Abstractions.dll'
Loading module Microsoft.AspNetCore.Authentication.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authentication.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authentication.JwtBearer.dll'
Loading module Microsoft.AspNetCore.Authentication.JwtBearer.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authentication.JwtBearer.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authentication.Core.dll'
Loading module Microsoft.AspNetCore.Authentication.Core.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authentication.Core.dll was not found or failed to read
Loaded Assembly 'System.Security.Claims.dll'
Loading module System.Security.Claims.dll in application domain 1:clrhost
Pdb file for assembly System.Security.Claims.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.DataProtection.dll'
Loading module Microsoft.AspNetCore.DataProtection.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.DataProtection.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.DataProtection.Abstractions.dll'
Loading module Microsoft.AspNetCore.DataProtection.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.DataProtection.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Cryptography.Internal.dll'
Loading module Microsoft.AspNetCore.Cryptography.Internal.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Cryptography.Internal.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.WebEncoders.dll'
Loading module Microsoft.Extensions.WebEncoders.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.WebEncoders.dll was not found or failed to read
Loaded Assembly 'System.Text.Encodings.Web.dll'
Loading module System.Text.Encodings.Web.dll in application domain 1:clrhost
Pdb file for assembly System.Text.Encodings.Web.dll was not found or failed to read
Loaded Assembly 'AutoMapper.dll'
Loading module AutoMapper.dll in application domain 1:clrhost
Pdb file for assembly AutoMapper.dll was not found or failed to read
Loaded Assembly 'AutoMapper.Extensions.Microsoft.DependencyInjection.dll'
Loading module AutoMapper.Extensions.Microsoft.DependencyInjection.dll in application domain 1:clrhost
Pdb file for assembly AutoMapper.Extensions.Microsoft.DependencyInjection.dll was not found or failed to read
Loaded Assembly 'DMS.Business.dll'
Loading module DMS.Business.dll in application domain 1:clrhost
Symbols for module DMS.Business.dll loaded
Loaded Assembly 'DMS.Data.dll'
Loading module DMS.Data.dll in application domain 1:clrhost
Symbols for module DMS.Data.dll loaded
Loaded Assembly 'DMS.Utilities.dll'
Loading module DMS.Utilities.dll in application domain 1:clrhost
Symbols for module DMS.Utilities.dll loaded
Loaded Assembly 'System.Linq.Expressions.dll'
Loading module System.Linq.Expressions.dll in application domain 1:clrhost
Pdb file for assembly System.Linq.Expressions.dll was not found or failed to read
Loaded Assembly 'Microsoft.OpenApi.dll'
Loading module Microsoft.OpenApi.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.OpenApi.dll was not found or failed to read
Loaded Assembly 'Portal.Business.dll'
Loading module Portal.Business.dll in application domain 1:clrhost
Symbols for module Portal.Business.dll loaded
Loaded Assembly 'Portal.Data.dll'
Loading module Portal.Data.dll in application domain 1:clrhost
Symbols for module Portal.Data.dll loaded
Loaded Assembly 'System.Runtime.Loader.dll'
Loading module System.Runtime.Loader.dll in application domain 1:clrhost
Pdb file for assembly System.Runtime.Loader.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.ApiExplorer.dll'
Loading module Microsoft.AspNetCore.Mvc.ApiExplorer.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.ApiExplorer.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authorization.Policy.dll'
Loading module Microsoft.AspNetCore.Authorization.Policy.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authorization.Policy.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Authorization.dll'
Loading module Microsoft.AspNetCore.Authorization.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Authorization.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Cors.dll'
Loading module Microsoft.AspNetCore.Mvc.Cors.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Cors.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.DataAnnotations.dll'
Loading module Microsoft.AspNetCore.Mvc.DataAnnotations.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.DataAnnotations.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Caching.Abstractions.dll'
Loading module Microsoft.Extensions.Caching.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Caching.Abstractions.dll was not found or failed to read
Loaded Assembly 'Swashbuckle.AspNetCore.Swagger.dll'
Loading module Swashbuckle.AspNetCore.Swagger.dll in application domain 1:clrhost
Pdb file for assembly Swashbuckle.AspNetCore.Swagger.dll was not found or failed to read
Loaded Assembly 'Microsoft.Extensions.Localization.Abstractions.dll'
Loading module Microsoft.Extensions.Localization.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.Extensions.Localization.Abstractions.dll was not found or failed to read
Loaded Assembly 'Microsoft.AspNetCore.Mvc.Razor.dll'
Loading module Microsoft.AspNetCore.Mvc.Razor.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.AspNetCore.Mvc.Razor.dll was not found or failed to read
Loaded Assembly 'System.Threading.ThreadPool.dll'
Loading module System.Threading.ThreadPool.dll in application domain 1:clrhost
Pdb file for assembly System.Threading.ThreadPool.dll was not found or failed to read
Loaded Assembly 'System.Collections.Immutable.dll'
Loading module System.Collections.Immutable.dll in application domain 1:clrhost
Pdb file for assembly System.Collections.Immutable.dll was not found or failed to read
Loaded Assembly 'Microsoft.EntityFrameworkCore.SqlServer.dll'
Loading module Microsoft.EntityFrameworkCore.SqlServer.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.EntityFrameworkCore.SqlServer.dll was not found or failed to read
Loaded Assembly 'System.ComponentModel.TypeConverter.dll'
Loading module System.ComponentModel.TypeConverter.dll in application domain 1:clrhost
Pdb file for assembly System.ComponentModel.TypeConverter.dll was not found or failed to read
Loaded Assembly 'Microsoft.EntityFrameworkCore.Abstractions.dll'
Loading module Microsoft.EntityFrameworkCore.Abstractions.dll in application domain 1:clrhost
Pdb file for assembly Microsoft.EntityFrameworkCore.Abstractions.dll was not found or failed to read
Loaded Assembly 'System.Data.Common.dll'
Loading module System.Data.Common.dll in application domain 1:clrhost
Pdb file for assembly System.Data.Common.dll was not found or failed to read

The entire log is too long to post, but this gives you a sense of the log I am looking at. As you can see, it almost seems like the entirety of .NET has disappeared. I tried both repairing and reïnstalling the .NET SDK as well as runtime, both to no avail. I have searched for all kinds of solutions, but all are either about one specific assembly or about something completely different.

I have been stuck on this for 2 days now and am completely stuck. Am I missing something? Have I done something wrong upgrading?

An important note perhaps is that I use JetBrains Rider for development and upgraded the solution in Rider as well.

Thank you in advance! Please do leave a comment should anything be unclear.