Error 1404 Could Not Delete Key Software Symantec
I tried your steps, but to no effect.
I went and found the registry entry listed in the error, and the permissions on it are such that I cannot even view the contents of the registry object. After taking ownership of the object, I can see that the entry does pertain to EDMarketConnector (it mentions filenames for EDMarketConnector's application files). After changing its permissions, then deleting it, I'm able to get past that error. However, a similar error then comes up identifying another registry entry, also with EDMarketConnector application files being mentioned.
Could not write value DebugFlags to key SYSTEMCurrentControlSetServicesGEFilterParameters. Verify that you have sufficient access to that key, or contact your support personnel. How to delete a 'blocked' Windows registry key using 'regedit.exe'.
All of the registry keys affected are named D36CE44061781964CBC011866B8B1242, so I will continue this process of finding them, taking ownership, and correcting permissions.
This last Windows Update (KB3140768) appears to have caused a handful of other little bugs in Windows 10. I'll put the blame there.
Error 1404 Could Not Delete Key Software Symantec Download
Once I've finished the ownership+permissions+deletion process on all of the affected registry entries, I'll write an update here.