Hello Matt Gorman
Thank you for reaching out to Microsoft Q&A Forum. I can see how disruptive it is when new Outlook suddenly starts asking you to sign in and then bounces right back to the sign-in screen.
To help me guide you better, could you please let me know: when it "crashes back", do you see any error message, or does it simply return to the sign‑in screen with no message?
Also, are you signing in with: a Microsoft account (Outlook/Hotmail), or a third‑party email (e.g.: Gmail/Yahoo)?
Here are some steps that you could try:
1. Force-close new Outlook and reopen
- Right‑click Start > Task Manager
- Select Microsoft Outlook > End task
- Reopen new Outlook normally and try signing in again
2. Repair the new Outlook app
- Start > Settings > Apps > Installed apps
- Find new Outlook > … (More options) > Advanced options
- Scroll down and select Repair
3. If it still loops, uninstall and reinstall new Outlook
- From Start, look for new Outlook for Windows > expand options > Uninstall
- Reinstall by opening classic Outlook and using the Try the new Outlook toggle to download it again.
Please feel free to let me know how it goes after trying these steps. Thank you for your time and understanding.
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