Hi Joyce Stranglen,
Welcome to our forum!
If you tried to pick up where you left off writing an e-mail message, it’s likely been saved as a draft automatically in the background. If something has changed with that draft that is different from the version you are working on “Operation cannot be performed as the message has been changed” pop up will occur. You may take the following ways:
- Copy the relevant part of the e-mail that you were writing.
- Close the e-mail message that you were working on.
- Go into your Drafts folder in Outlook and double click on the email in question (to put it into edit mode).
- Paste the text from the message you were just working on into it.
- Click SEND.
In addition, I found a similar thread that many people find tit useful, please feel free to refer to: The operation cannot be performed because the message has been - Microsoft Community
Hope it helps.
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