The NuGet package is created on disk, so this shouldn't be a permission problem. The matching .snupkg produces errors and is subsequently missing on disk and also not indexed.
API key is configured for both the package as well as the symbol source URLs.
.snupkg support is enabled on feed.
nuget.exe output:
D:\test>nuget push -Source https://192.168.x.x/nuget/nuget-hosted/v3/index.json SourceLinkTestLib.2.0.6.nupkg
Pushing SourceLinkTestLib.2.0.6.nupkg to 'https://192.168.x.x/nuget/nuget-hosted/package'...
PUT https://192.168.x.x/nuget/nuget-hosted/package/
Created https://192.168.x.x/nuget/nuget-hosted/package/ 231ms
Your package was pushed.
Pushing SourceLinkTestLib.2.0.6.snupkg to 'https://192.168.x.x/nuget/nuget-hosted/symbolpackage'...
PUT https://192.168.x.x/nuget/nuget-hosted/symbolpackage/
InternalServerError https://192.168.x.x/nuget/nuget-hosted/symbolpackage/ 67ms
PUT https://192.168.x.x/nuget/nuget-hosted/symbolpackage/
InternalServerError https://192.168.x.x/nuget/nuget-hosted/symbolpackage/ 7ms
PUT https://192.168.x.x/nuget/nuget-hosted/symbolpackage/
InternalServerError https://192.168.x.x/nuget/nuget-hosted/symbolpackage/ 56ms
Response status code does not indicate success: 500 (Internal Server Error).
Server log:
System.IO.FileNotFoundException: Could not find file 'C:\ProgramData\ProGet\Packages\.nugetv2\F1\SourceLinkTestLib\SourceLinkTestLib.2.0.6.snupkg'.
File name: 'C:\ProgramData\ProGet\Packages\.nugetv2\F1\SourceLinkTestLib\SourceLinkTestLib.2.0.6.snupkg'
at Microsoft.Win32.SafeHandles.SafeFileHandle.CreateFile(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options)
at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
at System.IO.Strategies.OSFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
at System.IO.Strategies.FileStreamHelpers.ChooseStrategyCore(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
at System.IO.Strategies.FileStreamHelpers.ChooseStrategy(FileStream fileStream, String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, Int64 preallocationSize)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options)
at Inedo.IO.FileEx.Open(String fileName, FileMode fileMode, FileAccess fileAccess, FileShare fileShare, FileOptions fileOptions)
at Inedo.ProGet.Extensions.FileSystems.DirectoryFileSystem.OpenReadAsync(String fileName, FileAccessHints hints, CancellationToken cancellationToken)
at Inedo.ProGet.Feeds.NuGet.NuGetFeed.InstallOrUpdateSnupkgAsync(Stream stream, Nullable`1 publishDate)
at Inedo.ProGet.WebApplication.FeedEndpoints.NuGet.NuGetApi.PutHandler.ProcessPutRequestAsync(AhHttpContext context, WebApiContext apiContext, RequestData urlData, NuGetFeed feed)
at Inedo.ProGet.WebApplication.FeedEndpoints.NuGet.NuGetApi.ProcessRequestAsync(AhHttpContext context, WebApiContext apiContext, NuGetFeed feed, String relativeUrl)
at Inedo.ProGet.WebApplication.FeedEndpoints.NuGet.NuGetFeedHandler.ProcessRequestAsync(AhHttpContext context, WebApiContext apiContext, NuGetFeed feed, String relativeUrl)
at Inedo.ProGet.WebApplication.FeedEndpoints.FeedEndpointHandler.FeedRequestHandler.ProcessRequestAsync(AhHttpContext context)