This issue just started happening the other day. The attached picture describes the issue better than I can write it out.
The issue goes away change the Windows user to my own user account so hopefully that will help narrow down the issue. I've also tried repairing the GP install. I've also tried copying over a working install from another user which didn't fix it either. Hopefully it'll be as simple as clearing out some temp files and letting GP regenerate them.
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