What step from TFS is that error coming from? It sounds like you’ve got some sort of PDB source indexing step that includes publishing those indexed PDBs to a symbol server?
Is there some way to configure an exclusion list for what PDBs are included in that step? It doesn’t really make sense to be trying to index and publish 3rd party PDBs. I would expect you to only be doing that for your own PDBs.
We have switched to portable PDBs for several reasons. They are much smaller than the traditional Windows PDB format. We are also source linking our PDBs via https://github.com/ctaggart/SourceLink, so that they already include all information necessary to step into our source when debugging.
In general, source linking can be looked at as the next step in the evolution of source indexing & symbol publishing, so I expect you’ll run across these more often in the future.
I’m not familiar with TFS, so I don’t know what level of configuration you have over that symbol publishing step. If it turns out that you can’t exclude our PDBs, there is a utility that can be used to convert between PDB formats that you could try out as a step before the publishing step: https://github.com/dotnet/symreader-converter