MS Teams return error code caa90017

New Contributor

Hi guys, I hope you're doing fine! 

I'm having a caa90017 error when trying to log in to microsoft teams.

I have tried all forms of contact and I have not been successful.


can you help me??

11 Replies

@adam deltinger thanks for this answer I'll see this now!

@BrennoClemente we've actually been running into caa90017 a lot these past few weeks too, but none of the suggestions in the linked thread there have helped. We've removed Teams, Office, cleared all caches and machine wide installers, installed Office with Teams, and it will sometimes be okay for 24-48 hours, and then the issue comes right back. Did you happen to find a solution that worked?

@adam deltinger 

The thread you linked has Literally nothing todo with the problem we are having in regards to caa90017.

I solved this error by closing Teams, going into %appdata%\Microsoft directory and renaming Teams folder (to "Teams.old" for example). When I opened Teams again, it failed and restarted. After that, Teams worked.

@glaucio It "solves" it until you reboot your computer or teams restarts itself for an update then it happens again.

@Jonathon Luken Is there any account connected on Settings > Accounts > Access Work or School ? Have you tried disconnecting it?
nope no account there or in cred manager.
best response confirmed by ThereseSolimeno (Microsoft)

For our issue, we found all of our errors of caa90017 were related to recent Teams updates, and Windows not being up to date - they were all running 1909 or later. An update to the latest Windows release later, and our problems went away. Prior to that, we had tried uninstalling Teams, removing the entire Teams folder and cache, reinstall, remove work or school accounts, etc. and it would, at best, get us a day or two before the issue came back. Updating Windows is what is solving it for us.

We have no more updates.. so now what do we do.. all our computer said they are up to date

@BrennoClemente try to right click on desktop icon go to properties/ compatibility/RUN THIS PROGRAM IN COMPATIBILTY MODE FOR : Windows 8