Hi @Catherine Cashman ,
Based on my test on O365 account, the color categories set by the client are synchronized to the web side.
Categories in Outlook desktop client:
Categories in Outlook for web:
I tried to reproduce your scenario and found that when the synchronization was slow, the color categories would be displayed in grey.
I refreshed the browser, and the color synchronization was successful. Please refresh your browser to check if the problem is solved. If the problem still exists, please provide more information for us to analyze.
- What type of account are you using? If you are using O365 account, does the problem occur in a personal mailbox or a shared mailbox?
- What version of Outlook do you have? Please provide specific screenshot.
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