+1 from me for this problem.

But it's a new problem I've never seen before.

I've only just started seeing it after upgrading to a new Mac. My OS is completely up-to-date (Catalina 10.15.6 and I'm running the latest Illustrator CC 24.2.1.

The only thing that has changed from my old system where I wasn't seeing this is that I'm using Google's GSuite Google File stream app.

I used to use their Backup and Sync app but decided to switch during my upgrade because I was so tired of Backup & Sync crashing all the time.

Judging by the fact that most people on this thread seem to be experiencing problems with OneDrive, I suspect there's something about the way the OS handles the sync with the file servers that's causing this problem.

I have this same problem saving to OneDrive. Currently running Illustrator 24.2.1.

It's still here with OneDrive – every time I save. No other software does this

same issue here with onedrive...

I cant believe such a large company still has all these bugs, good god, error messages after error messages, files not being saved properly, countless errors and formats that cant be opened messages. What in the world am I paying for, I feel like I am rolling the dice with each saved document, totally disrupting my business. And on the forum all we get is some person saying to update, when of course that's what we all did and keeps posting the same thing avoiding any real answer, come on Adobe!

I still regularly have this problem when I know no-one is working on my files. Running OS10.15.5 on updated Illustrator CC, saving to MS OneDrive.

still having the issue

Echoing recent comments in hopes of pinging this to Adobe's attention. Using MacOS 10.15.4 and Illustrator 24.1.2. I get this dialog every time I try to save (not Save As). Mostly annoying, but still.

I am also using Illustrator 24.1.2 and MacOS 10.15.4, and still have this prompt appear when saving an Illustrator project. Not completed at all by Adobe.... I wonder if they read this topic anyway....

I am using Illustrator 24.1.2 and MacOS 10.15.4, and still have this prompt appear when saving an Illustrator project.

Still happening in Illustrator 24.1.2 - macOS Catalina 10.15.4

Change that green COMPLETED flag to ******* IT STILL EXISTS AND MESSES UP WORKFLOW AND IS PROBABLY RELATED TO THE NEW CLOUD STORAGE MECHANISM THAT i NEVER USE ...

I'm getting the error using 24.1

Still a problem in Illustrator v. 24.1, Mac OS Catalina 10.15.3

And another one here. Happens every time I save to MS OneDrive. Adobe Illustrator v. 24.0.3, Mojave 10.14.6

Same here: Adobe Illustrator v. 24.0.3, OSX 10.15.3 (19D76) Catalina, saving to MS OneDrive.

Still having this issue.

Version 24.0.3

OSX 10.15.3 Catalina

Saving to MS OneDrive

Is it that hard to add a "don't show me this anymore"

Awful UX, is because of things like this that people end leaving for Sketch or other tools. Adobe, you are a huge company, SOLVE IT, it's been more than a year already.

Not fixed ... appearing every time I save.

MacOS Mojave version 10.14.5
CC 2020 illustrator version 24.0.3

This file has been modified outside illustrator. do you want to continue
Didn't had it for long but reappear recently almost every-time I wanted to save my files:
MacOS Mojave version 10.14.6
CC 2020 illustrator version 24.0.3