In Outlook for Mac, why wont the font wont changes from aptos despite signature settings

Hi Philip,

Welcome to Microsoft Q&A Forum!

Have a good day and I hope you're doing well!

Thank you so much for reaching out! I completely get how annoying that can be, particularly since new emails work just fine, and it feels like the settings aren't behaving as expected. Rest assured, I've replicated your exact scenario on a Mac virtual machine (including the signature tweaks you mentioned), and I was able to resolve it by adjusting a few key defaults. The good news is, this should get everything aligned to Century Gothic for you too. 

From what you've shared, this issue could stem from several factors, such as Outlook inheriting the format from the original email (often defaulting to Aptos), or the message being in Plain Text mode, which overrides font preferences. Even though your signature is set to Century Gothic, remember it only affects the signature block itself not the main message body. I hope the troubleshooting steps I've outlined below will help resolve this for you. I've tested them myself to ensure they're straightforward. 

Please try these steps: 

Set your default fonts for New emails and Replies/Forwards 

1. Open Outlook > Settings > Fonts 

2. Choose your preferred font (e.g., Century Gothic) for:  

New email 

Reply or forward 

3. Click OK to save 

Prevent inheriting the original message format and ensure HTML 

1. Go to Settings > Composing 

2. Turn off: “When replying or forwarding, use the format of the original message” (this stops Outlook from pulling in the original's font like Aptos) 

3. If you’re on the Legacy version of Outlook, please turn on: “Compose messages in HTML by default” (HTML is key here, as Plain Text ignores font settings altogether) 

Restart and test 

1. Quit Outlook completely (Outlook > Quit Outlook), then reopen it 

2. Try forwarding any email and check the toolbar. It should now show your chosen font (Century Gothic) for the new text you're typing 

A few helpful notes from my testing: 

• Your signature font only applies to the signature itself, which is why resetting it didn't change the main body. Outlook treats them separately. 
• Quoted content from the original email might still keep its own formatting, but your defaults will apply to anything new you add. 
• Some fonts like Century Gothic are more Apple-specific, so on recipients' devices without it, they might see a fallback font. For better cross-device consistency, common options like Arial, Calibri, or Times New Roman can help. 

In my virtual machine tests, these changes worked perfectly: after updating the settings and restarting, replies and forwards no longer defaulted to Aptos, and everything matched the custom font. If it persists for you, it could be due to not restarting Outlook after changes or that inheritance option still being enabled, causing the reply to "stick" to the original's font. 

If these steps don't fully resolve it, or if anything feels unclear (or if I've misunderstood part of your setup), just reply with details like whether you're using New or Legacy Outlook, your version, and maybe a screenshot of your Fonts and Composing settings. I'm here to help tweak it further and make sure it works seamlessly for you. No question is too small! 

Thank you for your patience, and I appreciate you reaching out. Looking forward to getting this sorted. 

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