"FileLoadException: Assembly is still being loaded." when running ASP.NET Core in script

mcintyre321

I have a script for running a minimal ASP.NET Core site in LINQPad, which used to work perfectly a few months ago (on a different machine, and probably an older version of LINQPad).

I now get:

Assembly is still being loaded. (Exception from HRESULT: 0x80131016)
  at Microsoft.AspNetCore.Hosting.WebHostBuilderIISExtensions.UseIIS(IWebHostBuilder hostBuilder)
   at Microsoft.AspNetCore.WebHost.CreateDefaultBuilder(String[] args)
   at Microsoft.AspNetCore.WebHost.CreateDefaultBuilder()
   at UserQuery.Main()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

The script is here: http://share.linqpad.net/s84g2a.linq

It happens in the line: `void Main() => WebHost.CreateDefaultBuilder().UseStartup().Build().Run();`. Any ideas? Thanks!

sdflysha

+1, I have the same issue and have no idea.

sdflysha

Do we have any fix/help for this? Very eager to use LINQPad to build a ASP.NET Core application.

alexjh

I performed a number of installations today and was able to witness this on one of our machines, but not two others. The only difference I observed is that a machine that had the .NET Core 2.2 preview installed ran into issues. Continuing to test.

alexjh

@sdflysha @mcintyre321 downloading the latest beta resolved this for me. I hope it works for you, too: https://www.linqpad.net/download.aspx#beta

JabenCAS

I'm having this issue and I *had* 2.2 preview installed at one point -- but uninstalled it -- but the issue won't go away. Rather frustration as I'm stuck on this one.

JoeAlbahari

Does it make any difference if you use the AnyCPU version of LINQPad?

JoeAlbahari

Also, try running the following query:
http://share.linqpad.net/ole7mo.linq

I've added a binding redirect in the app.config (press F4 to see it). The binding redirect shouldn't technically be required, but it appears that something weird is going on in the CLR.

mcintyre321

Hi Joe, I've installed the latest beta and it's fixed the problem. Thanks!

mcintyre321

Crazy - it stopped working today, with a slightly different message:

ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

and the LoaderExceptions contains:

Assembly is still being loaded. (Exception from HRESULT: 0x80131016)

  at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoadFrom(String assemblyFile, Evidence securityEvidence, Byte[] hashValue, AssemblyHashAlgorithm hashAlgorithm, Boolean forIntrospection, Boolean suppressSecurityChecks, StackCrawlMark& stackMark)
   at System.Reflection.Assembly.LoadFrom(String assemblyFile)
   at System.AppDomain.OnAssemblyResolveEvent(RuntimeAssembly assembly, String assemblyFullName)

I've tried downloading an even newer beta, but still getting it

mcintyre321

Just tried your binding redirect - that fixes it. thanks