Email in macOS 26 changing body text to Helvetica Fractions font

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Level 1

94 points

Email in macOS 26 changing body text to Helvetica Fractions font

Hello. After upgrading to macOS 26, emails from particular sender (but no other senders) are converted to Helvetica Fractions font, thus is unreadable. If I reply to the email, I cannot change the font in the original message. However, I can copy all the text, paste it into a word processor and change the font. It becomes readable again. Reading the email on my iPhone, however, is not a problem; no conversion to fractions.

I am assuming this is some sort of bug with macOS 26. This is not happening with emails sent by others.

[Edited by Moderator]

Mac Studio, macOS 26.0

Posted on Sep 23, 2025 6:22 AM

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Answer 1

Top-ranking reply

mhwill Author

Level 1

94 points

Sep 23, 2025 2:08 PM in response to Tom Gewecke

Problem solved!

I actually had a similar idea before I saw your response. I went to Font Book and looked at the Helvetica fonts. Then went into my Library : Fonts and removed the Helvetica Fractions Postscript font. That solved the problem. (Reinstalling the font made the problem reappear.)

I generally don't use the font, so I will probably keep it removed. The font came from a collection I bought from Adobe maybe 20 years ago. If I can find the original disk, I will reinstall it in case my installed version became corrupted. Doesn't answer the question of why this became an issue only after I upgraded from macOS 15 to 26.

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Answer 2

Sep 28, 2025 6:57 PM in response to joel6653_1

Did a little more snooping around on my system and found that it was the alien5.ttf font that was the issue. It incorrectly identifies itself as Arial, and I couldn't remove it through Font Book. But I found the file in the Library folder, moved it to trash, restarted the OS, and all emails are once again readable.

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Answer 3

Tom Gewecke

Level 10

122,484 points

Sep 23, 2025 1:47 PM in response to mhwill

First thing to try is going to Font Book > settings > advanced and reset fonts. This may remove the fractions font is it is in your system.

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Answer 4

Allan Jones

Level 9

79,148 points

Sep 23, 2025 9:40 AM in response to mhwill

Please tell Apple. They do not particilate in this user-to-user setting.

The proven way to effect changes is for enough people to report a bug to an Apple employee using this feedback link:

Feedback - Mail - Apple

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Answer 5

mhwill Author

Level 1

94 points

Sep 23, 2025 8:02 AM in response to mhwill

I have just had two more examples of email from other senders (beyond the one I mentioned in my earlier thread. In both cases, it appears that body text that is in the default font (sender's default? my default?) is being converted to Helvetica Fractions, but body text that is not using the default font, comes out fine.

Again, on my iPhone with iOS 26, all the email body text is fine. See screenshots of both.

[Edited by Moderator]

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Answer 6

Tom Gewecke

Level 10

122,484 points

Sep 23, 2025 2:18 PM in response to mhwill

mhwill wrote:

Problem solved!

Doesn't answer the question of why this became an issue only after I upgraded from macOS 15 to 26.

That may be connected with the content of those particular emails.

I’d recommend you not reinstall that font, as it is in a non standard encoding, can only cause trouble, and I think you would normally not want to use it in digital text except perhaps for local printing

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Answer 7

Sep 28, 2025 5:19 PM in response to Tom Gewecke

I do not have that font installed, and. as far as I can tell, never did. Since I don't know what the Helvetica Fractions font looks like, I don't know if this issue is exactly the same as mine, but Mail does have a strange, hard-to-read font in SOME messages (but not all). I can read it, but it's not fun or easy. It's probably just as annoying as the original poster's issue. Wish I could identify the font I get. Mail's settings (Fonts and Colors) are of no use or do not apply.

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