Office 365 Outlook 2013/2016 stuck "Synchronizing Hierarchy"

Question

Outlook 2013 or 2016 is not updating inbox.

However, all my email on the outlook on web online version and mobile apps is present.

On windows PC, I have clicked on "Update Folder" and "Show Progress". I see that 0 of 1 task have completed successfully. Progress is stuck at about 10%. and on the bottom of the window, it says "Synchronizing Hierarchy".

Initially outlook was syncing correctly, connected to office 365 normally, then configured outlook to use office 365 imap settings but still the same error.

What could resolve the error.

Answer 1

Hi @Benard Mwanza ，

Please go to File > Account Settings > Account Settings, double click the problematic account, if the checkbox of "Use Exchange Cached Mode" is selected, which means you are currently using cached mode, please clear the checkbox to switch to online mode, click Next, then reopen Outlook for the change to take effect and see if your inbox folder can update properly:

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