Outlook For Mac Not Syncing any Exchange info down.

Dear @Carson, 

Welcome to the Q&A Community.   

Thank you for your detailed explanation of everything you have already tested. I truly appreciate the effort you put in, and I understand how disruptive it is when Outlook for Mac won’t sync any Exchange data. 

Based on the symptoms you described, the issue usually comes from one of three areas: Conditional Access enforcement, a corrupted local Outlook cache for this specific account, or a Keychain token that is present but not usable. To help you move forward, please see the following workarounds that will help you verify the issue:  

Option 1: Refresh the local cache of this specific account 

This removes only the local copy of the account data on the Mac and does not affect anything on the server. 

Open Outlook > Go to Tools > Open Accounts and select the affected Microsoft 365 account. 

Select "Manage" in the lower left corner. 

Choose Reset Account and wait for Outlook to download the data again. 

This step targets corruption inside the account cache, which a full reinstall doesn't remove. 

Clear the cache in Outlook for Mac - Microsoft Support 

Option 2: Refresh macOS Keychain permissions for Office 

The Keychain may contain valid tokens that Outlook cannot use due to permission states. 

Quit all Office apps. 

Open Keychain Access > Select the login keychain > Open File > Choose Lock Keychain “login”. 

Open any Office app again. 

When macOS prompts for access, select Allow and sign in again if requested. 

This resolves situations where tokens exist but the system does not grant Outlook the required permission to use them. 

Office for Mac repeatedly requesting keychain access - Microsoft Support 

Option 3: Verify Conditional Access impact 

If your organization uses Conditional Access policies, the device may be blocked from syncing even if authentication succeeds. Policies such as “Require compliant device” can cause exactly the behavior you described. 

Note: If you are an end user, please contact your IT administrator for assistance with this step. 

For this step, your IT administrator will need to help by checking your sign in logs and confirming whether any Conditional Access policies were enforced on this Mac. 

How to Use Conditions in Conditional Access Policies | Azure Docs 

Option 4: Contact Microsoft Support 

Since you have already tried all actions available from the end user interface, the best next step is to ask your IT administrator to open a support ticket through the Microsoft 365 Admin Center > Support > Help & Support for further investigation.  

A technical support engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis.    

As community moderators, we kindly ask for your understanding that our access to internal development details is limited. Our primary role is to guide users toward the appropriate resources and support channels. While we may not have visibility into performing deeper backend analysis, we’ll continue doing our best to support you within the scope of our responsibilities.  

I hope this information is helpful. If you have any questions or need further support, please don’t hesitate to reach out at any time. 

Thank you for your patience and understanding. 

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