regdiff unable to create key

I find that running regdiff hangs, and the line in question yields:

+ k HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/WBEM/Transports/Decoupled/Client/{3D7F
34AB-9AAB-4E5F-846E-5EFB77EBC8C7} O:SY G:SY D:(A;;KA;;;SY)(A;OICI;KA;;;BA)(A;OIC
I;KA;;;SY)(A;OICI;KA;;;LS)(A;OICI;KA;;;NS) N/4lvQjKsqyK0p3oSraz2B+OH1Y=
>>> RETR FILE HKLMBASE.T HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/WBEM/Transports/D
ecoupled/Client/{3D7F34AB-9AAB-4E5F-846E-5EFB77EBC8C7}/values.bin
<<< 240 Retrieving file
<<<
<<< .
0 HKEY_LOCAL_MACHINESOFTWARE\Microsoft\WBEM\Transports\Decoupled\Client\{3D7F34A
B-9AAB-4E5F-846E-5EFB77EBC8C7} reg_get_handle RegCreateKeyExW != ERROR_SUCCESS

This is one of a number of keys that had this problem. I don't think this is any sort of restricted key. My basis for this determination is that I am migrating from PCRdist, and I ran a check against a Win 7 installation. This key is not one that it - PCRDist - ignores. Since that older program has been very reliable about which keys it can and cannot update, I am thinking that here, regdiff is somehow failing to do an update.
I am reluctant to start putting a lot of things in the reg negative transcript.

This is Windows 7, very basic install, running on a Dell GX270. ESET Antivirus in place; all automatic updates turned off.