Thanks for your reply. Yes, I created new backup sets when troubleshooting this problems, and yes, the problem PC was upgraded from Windows 7 to Windows 10. After remembering a similar problem with two other apps, I posted the following on the Microsoft Community...
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I have three computers running Windows 10. One was purchased new with Windows 10, and two were upgraded from Windows 7 to Windows 10. I found three applications, Microsoft Groove Music, Microsoft Photos, and Norton Security Backup, that do not run on one of the two computers that were upgraded from Windows 7, but work fine on the other two computers. These three applications share a common method that appears to be the root of their failure to run properly.
Each of these programs require you to navigate to a file or folder to select which files the program will use; music files in the case of Groove Music, photo files in the case of Photos, and the files to back up in the case of Security Backup. In Windows 7, these files were located in folders called My Music, My Pictures, and My Documents. In Windows 10, these folders were renamed Music, Photos, and Documents. On the PC that was upgraded and works properly, after navigating to the desired file or folder from within the applications, the resulting path that is shown within the application is correctly C:\Users\User\ Pictures\ or C:\Users\Public\Pictures\, or C:\Users\User\Documents\, etc.
The computer that does not work properly has one difference. The location of the user data is not on the C:\ drive, but rather on a different drive, F:\ , for space reasons. When this computer was upgraded, the name of the user data folders were renamed from F:\username\My Documents to F:\username\Documents\ and F:\username\Pictures\ , etc. But, for the three applications that are not working, after navigating to the folders located on the F:\ drive, the paths shown in the applications are F:\username\My Pictures\ , F:\username\My Music\ , and F:\username\My Documents\ . Since these paths and folders no longer exist, none of these application are then able to find the files they need, and they come up blank when they are supposed to preview the files. None of these applications allow you to edit the path. Navigating to the file or folder is the only way to select the file of folder.
Something must be telling these application to map the Documents folder incorrectly to My Documents, etc. I understand that the Documents and My Documents folders are Windows Explorer shell folders, and entries in the Windows Registry set the subkey that tells application the path to the actual folders and paths that are mapped to the shell folders. But I am not a Windows Registry expert, so I do not know how to correct this problem. Searching the registry, I do see a number of entries where the data field shows something like /F/username/My Documents/…
How do you tell windows to correct the incorrect mapping to the My Xxxx folders?
Thanks,
Tom