Ok. Let me clarify the issue. Its not that the application doesn't work at all. The attached picture shows the issue that I am having. The difference between the two being that (supposedly) when using the volume shadow copy service, you can copy files even if they are locked (because they are in use or other reason). However, since the volume shadow service method refuses to work, here is the line out of the log file for that particular backup attempt:
[1/28/2017 - 11:47:40 AM] Backing Up File: C:\Users\Administrator\ntuser.dat
[1/28/2017 - 11:47:40 AM] Result: Failed - Error: -1 (API Reg Save Failed (), Tried File Copy, File In use, Cannot copy.)
Thus, I am still trying to figure out how to get the volume shadow copy method to work correctly. For more information, look under the FAQ for Registry backup under "What advantages are there versus ERUNT?"