Hi fareed ashraf,
Thank you for reaching out to Microsoft Q&A forum.
This behavior can occur when Outlook has difficulty maintaining the connection with external email accounts such as Gmail. To help restore synchronization, please try the following steps:
1. Remove and re‑add the Gmail account in Outlook
- Remove the Gmail account from Outlook, then add it again. When adding the account, sign in using the Outlook sign‑in window that appears automatically. Do not enter the Gmail password directly into Outlook.
2. Check IMAP in Gmail
- Sign in to Gmail using a web browser, go to Settings > See all settings > Forwarding and POP/IMAP, and make sure IMAP is enabled.
3. Clear saved credentials
- Clear any saved Outlook or Gmail credentials from Windows Credential Manager, then restart Outlook and add the Gmail account again.
If the behavior continues, please let me know which Outlook version you are using so it can be checked further if needed.
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