Using classic Outlook for Windows in business environments
Hi @HMM
Thank you for posting your question in the Microsoft Q&A forum.
I understand this feature would be useful for you and other people; this will help you to manage your emails more efficiently.
Unfortunately, this is not available to flag unsent drafts at the moment.
You can use categories as an alternative to manage the drafts.
However, I know this is not your end goal. My recommendation is to contribute your feedback via Feedback Community.
Or you can vote for this idea which has the same feature as you want.
Flag Emails within a Draft Message prior to Sending · Community
Please vote here, Microsoft will listen and try their best to enhance customers' experience.
I hope this information helps.
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