Cached Exchanged Mode re-enable issues

[Splotchy0541]

In mitigating Searching Current Folder of an auto-mapped shared mailbox in Outlook Desktop returns no results or r...

we tested disabling cached exchanged mode which worked great but had the added downside of naturally forcing a connection to the exchange as a requirement.

This was to be expected.

What was not expected was on re-enabling old emails from 2020 appearing in outbox. How has this happened?

I also see no reason how this setting could have any impact on Microsoft Teams but an excited report included "I re-enabled this and now Teams stopped working". 

[#2]

Hi @Splotchy0541,

It is possible  that these older emails may not have been effectively synchronized or sent previously, and the reactivation of Cached Exchange Mode might have initiated a resynchronization, leading them to reappear in the Outbox.

Mail is stuck in outbox when using cached exchange and shared e-mail - Microsoft Community

Regarding the effect on Microsoft Teams, the direct correlation between reactivating Cached Exchange Mode and Teams malfunction is not so highly possible.
While Outlook and Teams are components of the Microsoft 365 suite, the impact of Cached Exchange Mode is limited to Outlook and its interaction with the Exchange server and not on Microsoft Teams.

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Kindest regards,

Leon Pavesic
(LinkedIn)

[#3]

We disconnected from the network before any of these emails could be sent.

Is it likely they would've been? Again these emails were not in the outbox before the setting change and were years old.

[#4]

Outlook Restart:

Close and restart Outlook. Sometimes, a simple restart can resolve connectivity issues.
OST File Repair:

Repair or recreate the Outlook Offline Data File (OST):
Close Outlook.
Locate and rename/delete the OST file.
Open Outlook to recreate the OST file.
Profile Recreation:

Create a new Outlook profile and attempt to enable Cached Exchange Mode in the new profile.
Check Group Policy:

Verify Group Policy settings to ensure they allow the use of Cached Exchange Mode.

[#5]

@cretecrocgmailcom To re-enable Cached Exchange Mode, first, ensure Outlook is closed. Navigate to "Control Panel," open "Mail," click "Email Accounts," and choose the account. Click "Change," check "Use Cached Exchange Mode," and click Next. If issues persist, create a new Outlook profile and repeat the process. Ensure your Exchange server and Outlook are updated.

[#6 · Accepted solution]

This was fixed in a platform update.