Teams 登入失敗 Error Code caa20002

 突然多位user的Teams登入失敗，錯誤代碼都是caa20002。

這些登入失敗的電腦，都是win7，但又不是每一台win7都有這個問題，有點奇怪。

後來找了幾台不同的電腦測試後，才發現原因。

主要是因為IE的關係，要IE11才能正常登入Teams程式，其他比較低階的版本，都會失敗。

很討厭的問題，因為錯誤訊息根本跟IE沒關係，很難查原因。

Teams Login Failure with Error Code caa20002

Multiple users suddenly encountered login failures in Teams, with the error code caa20002.

Interestingly, these login issues were observed on computers running Windows 7, but not every Windows 7 device was affected, which seemed puzzling.

After conducting tests on several different computers, the root cause was identified.

The problem primarily stemmed from Internet Explorer (IE) compatibility. Teams application requires IE11 to function properly, and lower versions of IE would result in login failures.

This issue was frustrating because the error message provided no indication of an IE-related problem, making it difficult to identify the cause.