Not able to send/receive mails in outlook app

[null null]

One user is not able to send/receive mails in outlook app. On browser he is getting mails.

sync process is getting stuck. I tried below steps but still facing same issue.

• scan.pst
• Work online and offline
• Disable adds-in
• Try outlook.exe /safe
• Office repair
• Created new profile
• Configured same Mail Id on another system
• Uninstalled and reinstalled Office

Please suggest what I can do to resolved this.

[#2]

I have seen some issues when users have a lot of items in Inbox folder (including inbox subfolders). I would say you should keep it to under 30k items, although MS documentation says 100k. https://support.microsoft.com/en-us/help/2768656/outlook-performance-issues-when-there-are-too-many-...