Mikey M, deleting Finder plst didn't make any difs for me.
I have just purchase a new iMac (Intel) running the latest BigSur and I have no issues. Quick View previews AI files just fine! My work iMac is stuck on High Siera and still not previewing. I have 2 coleagues working with BigSur but they can't preview AI files!
This is maddening!

@Yngve: ARTVIEW does NOT work with Big Sur and actually it does not seem, that this will be fixed. The website has not been updated for ages and I have been asking the Support, if/when Big Sur will be supported: Months ago they answered, that they are investigating, now they don’t even answer anymore. So ARTVIEW does not seem to be a solution anymore and waiting for a fix from Adobe is.... well... we all know.

I have given up on Adobe to fix this Quick Look support for their own files in MacOS. Just use this: https://www.code-line.com/artview/ It works instantly and It works on the news MacOS too.

3....years....later..... Almost $600 a year...

Yeah, this is annoying. The Mikey M fix works for me but sadly it doesn't last.

Also support Illustrator EPS files, please!

doesn't work and it's unfortunate

I could be wrong but that only helps for ai file when pdf compatibility is checked.
For native ai files without pdf checked I believe it does NOT work.

I've always been able to preview AI files in finder. But one day the feature just stopped working and I found this on an Apple thread that brought back the functionality:

1. Open to the Preferences folder of your home directory, or from Finder>Go>Go to Folder, copy & paste:
~/Library/Preferences/com.apple.finder.plist

2. Delete the com.apple.finder.plist

3. From the Finder icon on the Dock, hold the control option key and click the Finder icon>select Relaunch.

Hope this helps!

Has this been fixed yet?

I always save with pdf compatibility and I've never been able to see .ai Previews in the Finder.
The funny thing is that I've seen the icon working to show a preview with the ability to use quick view on my co-workers laptop which doesn't have any Adobe Applications (other than Acrobat) loaded on his system.

Is there a way to refresh the system to redraw previews for illustrator files in the Finder?
I've got thousands of files ... and I've got to open each one of these to see what the file is??????????????
WTF! That's a good use of time.

This really screws up my researching of old files. Every time you update something you break something else. This is really big deal for me.

Why should I pay someone else to look at Adobes files. I pay enough to Adobe I should be able to quick look at the files.. Adobe.. are you listening?? Just because ArtView 2 works doesn't mean its the correct way of doing things. Nice to see another company pick up the slack tho where Adobe has fallen short.

Why has this not been implemented already.. This is a basic fundamental MacOS feature that Adobe should support.!!

Art View 2 does that trick

Add me to the list for this as well. Saving files with the PDf compatibility slows the saving process WAY too much.

i want this also.. bridge can see the previews but the mac OS cannot

I think this has just been removed for the latest update to High Sierra (10.13.1)
It used to be great to quick look ai files and even eps. Please let me know if theres a fix
TIA