Using classic Outlook for Windows in business environments
Hi @Pitzer Amy
May I ask what is your Classic Outlook version> You can check this in File > Office Account > About Outlook.
You mentioned this only happens when replying to the specific sender, does the email body contain any suspicious format, links, signatures or images?
If you go to https://outlook.cloud.microsoft/mail/ and reply with that exact email, does it work?
If yes, this could indicate a render issue in Classic Outlook.
Please test if reply in plain text works. If it does, that means the content of the body has issue.
To reply in plain text: Open the reply email > Go to the Format Text tab > Click Plain Text.
This removes all HTML formatting (images, styles, hidden elements) and could help in avoiding the freeze.
If it works, you can consider setting compose message in plain text as default. Or manually set to plain text every time you reply to this specific sender.
To set this: File > Options > Mail > set to Plain Text.
Please try and let me know how it goes.
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