I really need to quit reading your posts when I first wake up lol
Mine throws no error. If this is a permissions issue, it could be the location of your project in the Windows folder structure. It may only allow Unity's native method of folder management.
I'm just attempting to clear the contents of MAST/etc/temp, so if there's a safer way than deleting/recreating the folder, please let me know.
Your post really was nightmarish to read on my phone though. I was joking but not really about bullet points before.