Unable to save project

I am using PLCnext engineer version 2025.0.3
I am using the template for the AXC F 2152. When saving this mostly empty project under
C:\Repos<projectFolder>, it works.
I sometimes get the error below when I have added a connection or code to the project and try to save it. Sometimes it’s after the first change and save, but sometimes multiple saves work and then after a while i keep getting the error.
When pressing „Yes“ in the dialog and selecting a new or different folder under the original location C:\Repos\ and saving it, i keep getting the same error.
image.pngI’ve looked in the logs but could not find a concrete solution

025-09-04 09:29:50.6823 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7108 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7111 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7113 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7114 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7118 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7119 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7120 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:50.7121 | Ade.Shell Error: { Id: 99 } : Unknown log entry domain 'D660E420-9BCA-4D3D-BC3D-BDE9FB3BD09F' 
2025-09-04 09:29:51.3964 | Ade.ComponentFramework Warning: { Id: 99 } : String resource not found: 'View.ToggleOnlineStatesUndocked' 
2025-09-04 09:29:51.5106 | Ade.ComponentFramework Warning: { Id: 99 } : String resource not found: 'View.ToggleOnlineStatesUndocked' 
2025-09-04 09:30:30.7029 | Ade.ComponentFramework Warning: { Id: 99 } : String resource not found: 'Main' 
2025-09-04 09:30:31.1253 | Ade.ComponentFramework Warning: { Id: 99 } : String resource not found: 'LD/FBD' 
2025-09-04 09:30:34.6910 | Ade.IO Error: { Id: 99 } : SolutionFileSystem.OnSaved could not be executed successfully : System.InvalidOperationException: Sequence contains more than one matching element
  at System.Linq.ThrowHelper.ThrowMoreThanOneMatchException()
  at System.Linq.Enumerable.TryGetSingle[TSource](IEnumerable`1 source, Func`2 predicate, Boolean& found)
  at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source, Func`2 predicate) 
  at Ade.IO.ChangeTracker.ChangesTrackerFileSystemDirectory.SynchronizeBaseConnection(IVirtualFileSystemEntryNativeObject nativeObject)
  at Ade.IO.ChangeTracker.ChangesTrackerFileSystem.SynchronizeBaseConnection(IVirtualFileSystemNativeObject nativeObject)
  at Ade.IO.ChangeTracker.ChangesContainer.FinishApplyChanges()
  at Ade.IO.ChangeTracker.ChangesTrackerFileSystem.FinishCommit()
  at Ade.IO.Implementation.VirtualFileSystem.OnSaved()
  at Ade.IO.Overlay.VirtualFileSystemDecorator.OnSaved()

image.png

I have the same problem from time to time. Check this thread and see if it is similar:

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