Project xcodeproj file can no longer by iCloud Sync

Thank you for your post and description. It appears that Apple Care support provided you with a valuable insight that seems to be the underlying issue.

Have you attempted to create a new project file using the latest version of Xcode? This simple test can help identify whether your project file contains settings that require correction. Additionally, I recommend verifying that you are logged into the same Apple ID on each device and checking the available iCloud storage to ensure it is not full.

Lastly, please ensure that you are utilizing the most recent version of Xcode, and identify the specific build version you are using.

While I still believe that creating a new Xcode project and incorporating your existing source files can be beneficial, as it may address underlying corruption issues, I concur with Apple Care Support’s assessment that the issue lies within your existing project.

Please let us know the results of your troubleshooting.

Albert Pascual
  Worldwide Developer Relations.

Thnak you for you quick reply. The problem occurred in a 3 years old project after updating to macOS 26.2 (25C56) and Xcode Version 26.2 (17C52).

I've created a new project : same error! All files synchronize except the .xcodeproj file.

There is 19GB free on iCloud Drive, and 59GB free on the Mac.

If I open the original .xcodeproj package file, copy all the included files in a folder outside, then they all synchronize on iCloud Drive except project.xcworkspace

Here are the attributes of this file com.apple.FinderInfo 32 com.apple.fileprovider.fpfs#P 4 com.apple.lastuseddate#PS 16 com.apple.macl 72

It's also a package, but the time if copied outside all its file are correctly synchronized to iCloud.

A feedback had been opened : FB21363976. It includes a zip with the file not syncing.

Thank you.

Thank you for your prompt response and for attempting a new project in Xcode. Your efforts are commendable, and I appreciate you filing the bug.

I started to think that could be some sync issues due a firewall or internet settings? Do you know when stopped working and the change was just a new version of Xcode or could be something related to the infrastructure?

In any case, the team for Xcode cloud is highly skilled and extremely nice as well and will swiftly identify the underlying issue. However, I kindly request your patience, considering the upcoming time of year and holidays. Your prompt attention to this matter is crucial for a timely resolution.

You can see the status of your feedback in Feedback Assistant. There, you can track if the report is still being investigated, has a potential identifiable fix, or has been resolved in another way. The status appears beside the label "Resolution." We're unable to share any updates on specific reports on the forums.

For more details on when you'll see updates to your report, please see What to expect after submission.

Again, let me thank you again for this. I added your FB in my list as well to keep an eye on it. Looking forward to a quick and successful resolution.

Albert Pascual
  Worldwide Developer Relations.

We know how bug reporting is important for good software quality. We use Feedback Assistant each time we encounter an issue. Then, we also know we never get progress reports, but we had a majority of issues solved. It's worth it.

Nothing changed in our infrastructure. The only changes were macOS 26.2 and Xcode 26.2. And has we had checked, and Apple Care rechecked, we have no other sync issues, just the .xcodeproj file, and now the new project .xcodeproj file.

I have updated the FB to include the zip of the file with the issue to help your Xcode team.

Thank you very much for you answers.