Can't open multiple instance of the editor without Linker issues

Development Platform & Builds
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1

So I’m building the engine from the source code and I’ve never had this issue before. I can’t open multiple instances of the editor; trying to do so gives me these link errors in Visual Studio:

LINK : fatal error LNK1104: cannot open file 'C:\Users\Filepath\UnrealEngine\Engine\Binaries\Win64\UE4Editor-Voice.dll'

LINK : fatal error LNK1104: cannot open file 'C:\Users\Filepath\UnrealEngine\Engine\Plugins\Online\OnlineSubsystemUtils\Binaries\Win64\UE4Editor-OnlineSubsystemUtils.dll'

So what changed between the working build and now? I actually did a few things:

  • Started using FASTBuild to decrease build times
  • Disabled a few built-in engine plugins to decrease build times and reduce disk size

But I never touched anything related to these dlls as far as I know. I removed FASTBuild and rebuilt the normal way and I got the same result. Reenabling the plugins I’d disabled didn’t help either. The .dlls are both there (otherwise I wouldn’t be able to open any editor instances) so I don’t know what could be wrong. Maybe there’s a messed up config file somewhere, but I don’t know what it would be.

2

I found a work-around for this. The problem seems to be caused by linking with VisualStudioSourceCodeAccess.dll – the plugin that handles Editor->Visual Studio communication. The two instances I need open are for different projects, and for one of them I disabled this plugin via the plugins window. This is super annoying that I can’t use the VS features, but at least I can have them both open.