Hi IgniteDanny
Thanks for your post in the community.
From your description, to verify the issue only associated to Teams client, your colleagues can sign in Teams web app to check the result. If they can access to the external group, then they are added in the group actually. Based on it, they can try to clear
the cache of Teams to check if it is workable. Kindly refer to the steps to clear:
- Fully exit the Microsoft Teams desktop client. To do this, either right click Teams from the Icon Tray and select ‘Quit’, or run Task Manager and fully kill the process.
- Go to File Explorer, and type in %appdata%\Microsoft\teams.
- Once in the directory, you’ll see a few of the following folders:
a. From within ‘Application Cache’, go to Cache and delete any of the files in the Cache location.
* %appdata%\Microsoft\teams\application cache\cache
b. From within ‘Blob_storage’, delete any files that are located in here if any.
* %appdata%\Microsoft\teams\blob_storage
c. From within ‘Cache’, delete all files.
* %appdata%\Microsoft\teams\Cache
d. From within ‘databases’, delete all files.
* %appdata%\Microsoft\teams\databases
e. From within ‘GPUCache’, delete all files.
* %appdata%\Microsoft\teams\GPUcache
f. From within ‘IndexedDB’, delete the .db file.
* %appdata%\Microsoft\teams\IndexedDB
g. From within ‘Local Storage’, delete all files.
* %appdata%\Microsoft\teams\Local Storage
h. Lastly, from within ‘tmp’, delete any file.
* %appdata%\Microsoft\teams\tmp
Besides, maybe the issue associated to the network environment. Therefore, kindly change the stable network environment to check if it works.
If you have anything unclear, please feel free to let us know.
Regards,
Joey