Cannot launch Outlook 365 offline - "the set of folders cannot be opened"

Windows 10 21H2 (OS Build 19044.1706) Office 365 2204 (Build 15128.20178) I'm unable to launch Outlook 365 offline. I get the error: "Cannot start Microsoft Outlook. Cannot open the Outlook wind...

office 365

ajkessel
May 20, 2022
Found a fix! Set created key in HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\AutoDiscover

DWORD ExcludeExplicitO365Endpoint = 1

Now I can start offline. As a bonus, Outlook also launches much faster.

ajkessel

Brass Contributor

May 20, 2022

Found a fix! Set created key in HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\AutoDiscover

DWORD ExcludeExplicitO365Endpoint = 1

Now I can start offline. As a bonus, Outlook also launches much faster.

PatrickEk

Copper Contributor

Aug 18, 2022

Thanks. This works for my users. I was not able to figure it out. Notice it affects more older version of outlook. Current ones don't have such Autodiscover issues.

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Cannot launch Outlook 365 offline - "the set of folders cannot be opened"

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