Using the New Outlook for Mac features in business environments
[Solution updated 05/07/2026]
Summary: OP has issue when use number list, a blank space got converted to extra number when the recipient replies to the email.
Solution: Make sure there is no space and use this button instead of manually type the number.
First, please go to https://outlook.cloud.microsoft/mail/ and check that specific email to see if it includes extra numbers.
If Outlook on the web render the email correctly (without extra number), it might be Mac client-specific behavior. You can try update your Mac to the latest version (16.108.3).
Does this happen to all emails that have numbered list or just this one?
Another possibility might be the recipient accidentally edit your original message while composing.
If possible, can you please provide the screenshots of your original email and the extra number email via private message?
I look forward for your reply.
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