Failed to Open Project. Opening the selected ArcGIS project failed. This project was saved using a new version of ArcGIS Pro <version>

Error Message

Opening an existing project file in ArcGIS Pro fails and returns the following error:

Failed to Open Project
Opening the selected ArcGIS project failed. This project was saved using a newer version of ArcGIS Pro <version number>.

In this example:

• Project created on 3.4 version
• Project opening on 3.5.1 version

Cause

Since the user is already working in a newer version of Pro, rather than the version in which project was created, the issue appears to be isolated to a single project, This suggests that the associated .aprx (ArcGIS Pro project) file may be corrupted. When attempting to open the project, an additional error may be encountered:

Failed to Open Project
Failed to open project <project name> unable to determine project type.

Solution or Workaround

As the project file appears to be corrupted, one workaround is to export the data from the existing geodatabase and import it into a new .aprx project.

1. Open a new project in ArcGIS Pro.
2. Make a folder connection to where the old .aprx file is saved. Navigate to <project_name>.gdb.
3. Right-click the file and select Export to XML document.
4. In the new project, navigate to the current project geodatabase (or create a new one). Right-click the geodatabase and choose Import > XML Workspace Document.

5. Once the XML document is successfully imported, all the data will be restored in the new geodatabase, and the new .aprx project can be saved.

Another workaround is to perform a clean uninstall and then re-install ArcGIS Pro.