From @onovotny on November 28, 2017 1:48

I’m seeing a regression that’s causing Ix.NET to fail with 2.0.3 and higher. I don’t know when the break was introduced. Nothing in Ix has changed related to this:
https://github.com/Reactive-Extensions/Rx.NET/tree/develop/Ix.NET/Source

Getting errors like this:
"C:\dev\RxNET\Ix.NET\Source\System.Interactive\System.Interactive.csproj" (pack target) (1) ->
(GenerateNuspec target) ->
C:\Program Files\dotnet\sdk\2.1.1-preview-007165\Sdks\NuGet.Build.Tasks.Pack\buildCrossTargeting\NuGet.Build.Tasks.Pack.targets(204,5): err or : The file 'C:\dev\RxNET\Ix.NET\Source\System.Interactive\bin\Release\net45\System.Interactive.pdb' to be packed was not found on disk. [C :\dev\RxNET\Ix.NET\Source\System.Interactive\System.Interactive.csproj]

And the build log shows this:

This is in error because there are no symbols for DebugType = embedded. The build log clearly shows DebugType set to embedded.

msbuild.zip

Copied from original issue: NuGet/Home#6230