I appreciate your efforts.
Let's remove the admin access for now.
Open the elevated prompt, type in
net user administrator /active:no
Then close the elevated command prompt box.
Difficult registry merges that appear to not have sufficient privileges.
If you need it here is the BITs.reg file again:
BITS.reg 6.14KB 94 downloads
1.Download PsTools,extract from this psexec.exe file and put it in C:\Windows\System32
2.Download fix for BITS service to your desktop.
3..Run cmd.exe with administrative privileges (right click on cmd.exe and choose "run as admin") and type:
psexec -s -i -d C:\WINDOWS\regedit
//This command runs regedit from System account.//
4.Go to File>>Import choose location where you stored BITs.reg file,choose it and apply.
Once restarted try to update and let me know the outcome.