Microsoft Teams Troubleshooting

Microsoft Teams is an ever evolving platform and their apps for Windows, Linux (yes, you read right), macOS, iOS and Android are constantly being updated to reflect new features and improvements. 
At times, the Teams app can misbehave; it can happen with Teams renames, people's attributes like title updates, access to Team sites not applying or just the app itself crashing, failing to sign in, etc...

While these are rare events, it can be disruptive especially if Teams is one of your primary collaboration tools. Whenever you are experiencing an issue with Teams or other Microsoft 365 service, it's best to check whether there is an outage; a good place to start is the Microsoft 365 Service health status if you manage a Microsoft 365 tenancy or Downdetector as an end user.
If there is isn't any reported outages, start troubleshooting locally; at a minimum, ensure you have updated to the latest release, try signing out and back in, terminate teams.exe or restarting are less invasive approaches. 

An alternative to the app is Teams online via I find it offers a near like user experience compared to the app, though it's not without its shortcomings.
At the time of writing, I couldn't request control from a remote participant of a video call and sharing my screen turns my camera off. Microsoft are likely to address these minor issues over time. 
If it's the web version that is giving you grief, try accessing the site in Incognito/Private mode, or simply clear your browsers cache.

If the Teams app for Windows is the culprit, you might need to flush the local cache it stores under your Windows user profile, specifically these paths:

  • %AppData%\Microsoft\teams\application cache\cache 
  • %AppData%\Microsoft\teams\blob_storage 
  • %AppData%\Microsoft\teams\databases 
  • %AppData%\Microsoft\teams\cache 
  • %AppData%\Microsoft\teams\gpucache 
  • %AppData%\Microsoft\teams\Indexeddb 
  • %AppData%\Microsoft\teams\Local Storage 
  • %AppData%\Microsoft\teams\tmp 

You can run the following as a batch script in Command Prompt to purges these folders:

start /wait taskkill /F /IM teams.exe
start /wait taskkill /F /IM OUTLOOK.exe
ping -n 5 localhost > nul
del /q /s %AppData%\Microsoft\teams\application cache\cache
del /q /s %AppData%\Microsoft\teams\blob_storage
del /q /s %AppData%\Microsoft\teams\databases
del /q /s %AppData%\Microsoft\teams\cache
del /q /s %AppData%\Microsoft\teams\gpucache
del /q /s %AppData%\Microsoft\teams\Indexeddb
del /q /s %AppData%\Microsoft\teams\Local Storage
del /q /s %AppData%\Microsoft\teams\tmp
del /q /s %AppData%\Microsoft\teams
%LOCALAPPDATA%\Microsoft\Teams\Update.exe --processStart "Teams.exe" --process-start-args "--profile=AAD"

If you want to delve into the logs for errors in Windows, press [Ctrl] + [Shift] + [Alt] + [1], which will generate a diagnostics log file.