failing to open

The context does not identify a single confirmed root cause for the recurring "We detected a problem launching the new Outlook. Please try again later." message in new Outlook for Windows. The supported causes and patterns are:

1. Local new Outlook app state can become corrupted Accepted troubleshooting for this launch problem includes clearing the local new Outlook data by deleting the Olk and OneAuth folders after closing Outlook and other Microsoft apps. Those folders are recreated when the app starts again.
2. The app installation or app state may need to be reset Supported steps for new Outlook issues include:
   • End Microsoft Outlook in Task Manager
   • Reopen it
   • If needed, uninstall and reinstall new Outlook for Windows from the Microsoft Store
3. Some launch failures are service-side or account-data related rather than device-only problems One documented Q&A resolution describes a startup failure during StartupData as typically occurring when new Outlook cannot load account data from the service. That indicates some launch issues are tied to account or server-side conditions, not only the local PC.
4. Temporary product issues can also affect Outlook startup Microsoft has documented cases where Outlook launch failures were under active investigation and advised using Outlook on the web temporarily while the fix propagated.

Because the issue happens about once a week and affects calendar access, the most supported explanation is a mix of intermittent new Outlook app-state corruption or a temporary service/account-data loading issue.

A practical supported path is:

1. When it happens, end Outlook completely
   • Right-click Start > Task Manager
   • Select Microsoft Outlook > End task
2. If it keeps recurring, clear the local new Outlook state
   • Close Outlook and other Microsoft apps
   • Delete these folders:
     • C:\Users\<UserName>\AppData\Local\Microsoft\Olk
     • C:\Users\<UserName>\AppData\Local\Microsoft\OneAuth
   • Restart Windows
   • Open new Outlook again
   Note: these folders are recreated automatically.
3. If still recurring, reinstall new Outlook for Windows
   • Start > Settings > Apps > Installed apps
   • Uninstall new Outlook for Windows
   • Reinstall it from the Microsoft Store
4. Use Outlook on the web when the issue is active That is the documented workaround in Outlook issue investigations and avoids losing calendar access while the desktop app is failing.

References:

• Outlook for Windows not responding, hangs, freezes, or stops working
• Detected a problem launching new Outlook - Microsoft Q&A
• can't use new outlook - Microsoft Q&A
• outlook wont open - Microsoft Q&A
• Active Investigation into Outlook Crashing on Launch