Error 646 can be one of the most annoying error messages seen. This is typically an error code that comes to Windows operating system users when they are attempting automatically install an update. The error 646 will typically arise if there are conflicts within the operating system, lack of current Windows programs or many other various things. Listed below are some ways to help assist with the error 646, please keep in mind that some of these are higher technical levels than many users feel comfortable with:
The first option to avoid getting error 646 is to avoid automatically updating the operating system itself. This can be done by locating the source of the update and manually updating the sytem.
The second option on how to avoid getting error 646 is to try to Disable the UAC, which stands for User Account Control, within the operating system. This will then remove power from the users. Once the UAC is turned off try to download and install the updates as the administrator to avoid getting the error 646 code.
If these actions did not assist with removing the error 646 when updating there is a possibility that there is a bad piece of software, like a virus, on the system that is stopping the updates. If you suspect this could be the cause the best thing to do is to restart the machine in safe mode and run a full system scan. Remove any identified malware and restart the system in normal mode. If the error 646 continues to pop up after removing the software then it is best to run a registry cleaner through the machine to ensure that all aspects of the virus or malware have been removed. There is a chance that if the malware left pieces in the registry this could be the cause of error 646.