In the case you experience slow sending and/or receiving of emails with Outlook 201x try one of the options below:

  • Enable Outlook with Cache

    • 'Mail to keep online': set to 'All'

  • Start Outlook in Safe modes (outlook.exe /safe)

  • Or try with disable Outlook Cache

  • Create a new Outlook Profile

  • Does the computer has the latest patches/updates?

  • Test account on another computer with Outlook

  • Check your hard drive for bad sectors

  • Temporary disable Anti-Virus , restart Outlook and try again

  • Is domain complete installed / validated in Office 365 Admin center?

 

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