Sync Issues \ Local Failures in Outlook

Given the size of the folder, I'd suggest recreating the Outlook profile as a faster/easier solution. You can keep the old profile, just in case.

Hi @Cloud_Geek_82 ,

In Outlook - Folders I found Sync Issues folder and deleted a number of synchronization failure logs but the number of sync issues \ local failures in folder size statistics isn't changing.

Have you tried checking checking the Folder size by right clicking the Local Failures folder, choose Properties > Folder size and see if the size there had been shrinked:

Besides, please try compacting the OST file via File > Account Settings > Account Settings, double click the account, click More Settings... > Advanced > Outlook Data File Settings > Compact Now:

In case the issue persists, I'd suggest trying to make the OST file recreated by exsiting Outlook, go to "C:\Users\<username>\AppData\Local\Microsoft\Outlook", delete the OST file for the account, then restart Outlook to force the recreate of the OST file.

Should it still doesn't work, agree with michev that you can create a new Outlook profile and check the result.

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