Summary
This article describes steps to try if your conditional formatting rules in the Microsoft Outlook Desktop App for Windows suddenly stop working.
Environment
Microsoft Outlook Desktop App for Windows
Issue
You had conditional formatting rules set up in Outlook for Windows, to change the font, color, bold, etc. of messages meeting certain criteria (such as addressed to a specific distribution list, or with a particular Category tag applied), but suddenly, they stopped working and all messages look the same in your Outlook (Windows) Inbox or folder View.
Resolution
Step 1 - Open Outlook
Step 2 - Go to the File tab
Step 3 - Select Options
Step 4 - Select Add-ins near the bottom
Step 5 - Next to Manage Com Add-ins click the Go button
Step 6 - Make a list or screen shot of which Add-ins are checked, so you know which you had in case you need to turn them on again later.
Step 7 - Un-check all of the Add-ins
Step 8 - Click OK to save the changes
Step 9 - Close and re-open Outlook
Step 10 - Check the conditional formatting to see that it is working again
Step 11 (Optional) - Re-enable each add-in as needed
Result
Your conditional formatting rules in Outlook for Windows should function again.
Further Readings
Microsoft Support - Conditional Formatting in Outlook: Automatically change incoming message colors and fonts based on sender, subject, or recipients
Need additional help?
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