Fonts changing in files when opened in Illustrator 29.5.1

The bug is still present in 29.7 using M1 Max OS 15.5 with Connect Fonts managing fonts.

Plus one. I cannot use a beta version of any software on the work machine. Went back to 29.4. We have too much going on to mess with this. 

The adobe update teams strikes again, thank you for releasing with a MAJOR bug. No one can stay in business and keeps raising prices like like adobe for a bad product.

I have ran into this same issue before upgrading to Illustrator 29.6.1 and today it has happened again. When I opened a file I worked on previously about a month ago, it has completely wrecked my file, changing all my text to random glyphs! I cannot even salvage the file by retyping the correct text as it continues to input the same random glyphs and not the appropriate letters! This is a HUGE problem! Thankfully in this instance it's a simpler design and I had the artwork saved in a separate proof file with the fonts converted to outlines otherwise I would have had to completely rebuild. If the client comes back at a later date wanting, changes to their file.....I'm screwed and will have to rebuild it so I can edit it. This is a catastrophic issue and if it begins to happen more frequently especially with bigger/complex design files, it will kill the software from a professional standpoint. This must be resolved ASAP.

I'm working on a packaging project and have maybe a mix of 10-15 fonts that I'm using within the document. I closed the file last night, and when I reopened this morning every font within the document was changed. I'm working from my desktop and I'm the only one using this computer. It appears to be some kind of bug. What's interesting is that all of the fonts are still using the same 10-15 fonts that I've been using, but none of them are in the correct places. It's as if they've all rotated. I've tried running updates, but there aren't any. I've uninstalled an reinstalled the fonts. I've closed and restarted. Nothing. I've got a meeting with this client in 10 minutes. It wouldn't be a huge deal if this were just a couple of designs, but I've got 20-30 layouts that I need to fix now. I've never seen this before.

I have encountered a bug in Adobe Illustrator after updating to version 29.6.1. Some of the design files I had previously worked on are now experiencing font-related issues. For example, fonts in some files have changed — a file that originally used Font A is now showing Font B when opened. Additionally, in files where bold text was used, the text now change to regular type when opened in this version.

Please kindly address and resolve this issue as soon as possible. Thank you.

I keep getting emails sent to me on this topic about folks trying various versions of Illustrator 29.5.whatever, and 29.6.whatever.

No.  Don't do that.  Both of those versions have this random font substitution bug, and it has not been fixed.  You have the potential, using those versions of Illustrator, to lose days worth of client work instantly, costiing you untold re-work hours and dollars.

Just revert back to 29.4 and you will have no issue.  Then wait the weeks, months, or years that it takes for this devastating bug to be fixed.

This has happened to me a few times recently and it's really disconcerting. Right when i go to release mechanical files.

You're not alone. The same thing just happened to me. Frustratingly, to a file that contained 50+ individual designs. No new fonts were entered into the document, but the fonts essentially all switched with each other. Makes no sense and is incredibly frustrating. Hope they fix this bug quickly. 

I've had to reinstall an earlier version of Adobe illustrator 28.5 - and it seems to be doing the trick at the moment, but still not great having to backsave!!!