Classic Outlook mail merge hangs trying to initialize Word

Last Updated: April 8, 2025

ISSUE

When you initiate a mail merge by using contacts as a data source Outlook hangs at Initializing Microsoft Word.

Outlook Mail Merge hangs at initializing window

STATUS: INVESTIGATING

The Outlook and Word Teams are investigating the issue. We will update this topic when we know this issue will be addressed.

WORKAROUND

Workarounds until a fix:

Disable COM add-ins in Word. In some support cases a Word add-in is triggering the issue. Use this topic to temporarily disable a Word add-in, Load or unload a template or add-in program. After you disable the Word add-ins, restart Word to pick up the change before proceeding with the mail merge.
Start classic Outlook by running as Administrator context and then do the mail merge. Some users in the community found this worked for them. After you are done with the mail merge restart Outlook back to normal mode.
Start classic Outlook by running as Administrator context and then restart Outlook back to normal mode and then do the mail merge. This may cause permissions and settings on files and the registry to update properly for mail merge to work.
Start mail merge in Word and filter for contacts there, Use Outlook contacts as a data source for a mail merge.
Export contacts to an Excel CSV file to run the mail merge in Word, Mail merge using an Excel spreadsheet.