Sometimes, she can log in to one of the Office apps, but when attempting to open another app, it either gets stuck loading or prompts for login again with the CAA50021 code. We have tried the following steps: Removed all credentials from credential manager. Checked Azure AD to ensure nothing was blocking the client from signing in., Outlook suddenly asked for password for first time since I first set up PC in Dec 2024. Password correctly entered many times (checked it every time before submitting it - Caps Lock off so that's not the issue) but I keep getting "Sign In Failed". Email is sending/receiving fine on all other devices including email provider's own website., Hello, I have a very strange issue when logging into Outlook for windows I get several attempts to login per second or any interaction within the app to try, Outlook - subject change does not reflect Good afternoon, There's two of us using the same email (gmail) on 2 different Outlook : 1 on PC and 1 on Mac. When i change the email subject, it reflects automatically but when my colleague does on her Mac, it does not show. From Mac : see, she has changed the subject to "handled by CC" but it does not reflect on my PC Any idea why ? Many thanks in , Intune Mobile Outlook Asking password again and again we have some of the mobile users which is having issue with outlook signin . After enrollment of the device user is not able to sign in in the outlook it seems like it is stucked in the loop. however teams is working fine for these users., Figure 2 Sign-in using Outlook Android app Figure 2 Sign-in using Outlook Android app Note that if you already have Microsoft Authenticator configured on your phone, you can continue to use it to sign in. Support and Resources To learn more about the new Outlook sign-in verification feature for Microsoft account and for support, click here..