How to fix windows update error code 646?

What is windows error code 646?

 When you try to update windows then you might have received an error message code 646 on your windows screen and unable to update windows. Windows update has become very common problem for system users.  Windows update error generally occurs due to improper maintenance of your system. It generally happens that we try to tease windows registry files even after not knowing it properly. Windows error code 464 is also called 0x80070646 which is generated by Windows Installer. This error occurs due to the incorrect value in present in windows registry. We generally avoid this error but if we keep avoiding it then it can damage your system files as well as your installed operating system. You will observe this error affects similarly in all versions of Ms Windows. We should try to fix this windows update problem.

Why this error occurs?

 This error occurs due to missing of some important files from windows registry keys, when your system is fully infected by virus then you receive this kind of error message, incomplete updates of windows, software that you have installed that may be outdated.

What are the symptoms?

Error Code: 0x80070646 or
Error Code: 646 
or
 Error 1606 Could not access network location %APPDATA%” you receive this error message when you try to update windows.
or
Windows update error code 646 reports that you are unable update windows and you may face many several system problems.

How to fix windows error code 646?

 I can fix my PC by following given below steps:-
To fix this error we need to verify the value of the AppData key which is present in the windows registry and to work on this operation follow the steps:-

• Click on start button and type regedit in the start search box and press enter.
• When the program list will appear, then right click regedit.exe and from there click Run as Administrator and then click on continue option.
• Navigate and click on the following registry subkey:
• HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders and in condition if the value is not set to %USERPROFILE%\AppData\Roaming  then right click AppData from the details pane and then click on Modify option.
• In the Value data box enter %USERPROFILE%\AppData\Roaming  and then click ok.
• Then close registry editor and try to update again.
• If you receive again this error after following given above steps then repeat the above same steps instead use the following  registry subkeys HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders
• HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders and repeat the same steps.

You can also use third party repair tool to fix windows update error code 646.