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Please copy your projects from the its original location to any other location. By default all the projects recorded in Video Express get saved at the location mentioned below.
C:\Users\rasaini\Documents\My Adobe Presenter Video Projects
You may try to copy all of your projects from this location to any other location like D drive or desktop.
Once all the projects are copied then you may delete them from their default location.
Then try to import the project from the new location. Please click on settings and then choose import project and choose the new path to open the project.
Try to delete some existing project and then try to import.
Is it happen with a specific project or all of your projects.