For Microsoft Outlook to communicate with Google Workspace using the MAPI protocol through Google Workspace Sync for Microsoft Outlook, and for the mapped drive of Google Drive for Desktop to accept files to be synchronized with the Google Drive service, your Advanced Data Loss Prevention > Data loss prevention service protection needs to allow certain channels and addresses so that this communication can occur without interference:
The following addresses must be allowed in the "Allowlist for remote hosts" session; they can be declared on a single line, as follows:
www.googleapis.com/generate_204; www.google.com/accounts/; www.google.com/accounts/ClientLogin; apps-apis.google.com/a; www.google.com/m8; mail.google.com/mail; *.googleapis.com; oauth2.googleapis.com/token; accounts.google.com/o/oauth2; www.googleapis.com/oauth2
The following items must be allowed in the "Allowlist for applications" session:
*\googledrivefs.exe
*\outlook.exe
After authorizing these communication channels, the errors and synchronization issues with Microsoft Outlook using GWSMO and Google Drive for Desktop should disappear.
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