outlook not saving the capitalization of first word sentences on macOS tahoe software

Hi @Edgar Garcia,

Welcome to the Microsoft Q&A forum.

I’m sorry that you’re experiencing this issue.

I attempted to reproduce the issue in a test environment and encountered the same behavior. In Outlook for Mac version 16.108, the first letter of sentences is no longer automatically capitalized. I also found that multiple Mac users have reported similar behavior, which suggests this may be a broader product issue rather than an isolated configuration problem.

In this case, I recommend sharing this issue with Microsoft’s product development team. Submitting feedback will help the development team identify and review the issue, allowing them to pay closer attention to it, conduct further investigation, and provide the latest updates or information regarding this behavior.

Outlook · Community

If you have any other questions or concerns, please feel free to share them. I’ll do my best to assist within my capability.

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none of these worked. i also cant use editor button on my outlook. i believe that is a different type of microsoft work/office/365 software.

In new Outlook for Mac, sentence capitalization is controlled by the Editor/AutoCorrect settings inside Outlook, not by macOS keyboard settings. macOS “Capitalize words automatically” does not override Outlook’s own Editor behavior.

To re‑enable automatic capitalization in new Outlook for Mac:

1. Open a new email (or reply to an existing one).
2. On the ribbon, select Editor > Editor Settings.
3. In the Editor pane, use the toggle to turn autocorrect and auto capitalization on.
4. Close the Editor pane and test by typing a few sentences.

If using classic Outlook instead of the new Outlook experience:

1. Go to File > Options > Mail > Editor Options.
2. Select Proofing > Autocorrect Options.
3. On the Autocorrect tab, make sure Replace text as you type is selected.

On Outlook for Mac (classic UI):

1. On the Outlook menu, select Preferences > AutoCorrect.
2. Select Replace text as you type.

If capitalization still does not work after confirming these settings, test in another profile or Outlook identity to rule out profile corruption, and ensure Outlook is fully updated to the latest build available for Tahoe.

References:

• Autocorrect, auto capitalize, and auto format your messages
• Turn AutoCorrect on or off in Outlook for Mac