I was doing a repair on Visual Studio 2015 and it seemed to be stuck at the end, installing an Android emulator IIRC. I killed the installer and fired up VS and saw a very practical error message:
Repair/Modify operation did not finish successfully. Please repair Visual Studio before continuing. You may continue to run Visual Studio, but operation may not be reliable.
But I had work to do and was pretty confident that VS in its current state would take me through the day. I had to jump between a couple different projects that day and each time I would see:
How do I disable this message box? Registry Hack Time! Here’s the PowerShell script I used. (I like PowerShell)
Of course, at some point I’ll have to rerun the repair, but this got me back to work!