Using the New Outlook for Mac for personal email and calendar
Hi, Brandon Ellison
This draft acknowledges that the Gmail data is safe, avoids repeating the extensive troubleshooting already completed, and focuses on escalation with diagnostic logs.
The fact that all messages remain available in Gmail, the iPhone, and Thunderbird confirms that the emails have not been deleted. A large Gmail mailbox can take several days to download fully, but the Inbox becoming empty again after syncing is not expected and points to an Outlook for Mac synchronization or display issue.
Here are some suggestions you can try:
In Gmail on the web, open Settings > See all settings > Labels and confirm that Show in IMAP remains enabled for Inbox and All Mail. Then return to Outlook and select Sync.
Since you have already reset the account, rebuilt the profile, and performed a clean installation, I would not recommend repeating those steps.
In Outlook, select Help > Contact Support, describe when the Inbox becomes empty, and allow Outlook to collect diagnostic logs. These logs are important because the issue returns after the initial synchronization and may not be visible while Outlook appears to work normally.
Until the issue is investigated, continue using Gmail online or Thunderbird so you have reliable access to the mailbox.
Thank you for your patience in reading, I hope this information has been helpful to you.
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