I found a solution to this problem (it helped in my case, I was programming on another computer and at home project opening the same error occurred)
The solution is as follows:
1. Open the project, do not click "OK" in the dialog box.
2. Open Task Manager, and shut down VisiLogic.
3. Restart the project, use recover, and click OK 2 times (in 2 dialog box).
4.Your project is open.