Tell us the account you want to use to open _vti_rpc.

How can you go back to the previous version of Office?

The reply from this thread (also mentioned here) about deleting your cached credentials solved the dialog box problem, but now I have a much worse problem. Now every time I open a document for the first time since the update that introduced the _vti_rpc dialog box, Word hangs and I have to kill the process. Second time I open the doc it's fine, but for someone who works with Word docs all day long, this has crippled my productivity.

So consider how annoying it is to X out of the authentication prompt (which is harmless) vs. how annoying it would be to have Word hang every time you open a doc for the first time. If you mostly work with the same docs over and over, it might be worth doing the above solution.

This solved the dialog problem but now Word hangs every time I open a document the first time, new or old. :(

I decided to try on my other workstation, same OneDrive accounts connected, same office 365, Autosave also disabled and greyed out. Problem was unfortunately not resolved. I would really like a response from Microsoft, perhaps I can supply more logs or more information which would be beneficial to resolving this issue.

not working for me. I continue receiving the pop up when closing any word document.

Office was upgraded and now the autosave is off and greyed out.

the problem continues.