I have run into this issue a lot in the past few months and I think it deserves a post.
Here’s the scenario:
A user who tries to create a local file and encounters this error. They cancel it and re-try it again and still generate the same error. Immediately, they think it is a network issue because that’s what the warning is saying “This could be due to a network problem. You can try again or contact technical support.”
I got the call from the user and I tried to resolve this issue remotely (or in person sometimes). I asked them to reproduce the issue and notice they already have a local file previously created in the local drive and therefore Revit asked if you want to “Overwrite existing file” or “Append timestamp to existing filename” like the image below. They chose the latter. This is where they got the same warning again.