Jul 8, 2011 14:22 GMT  ·  By

An automated fix is available from Microsoft for issues generating error codes such as 0x80070646, 646, or 1606.

The software giant has confirmed a problem impacting the Windows Installer and affecting customers attempting to use either Windows Update or Microsoft Update.

“This update problem occurs when Windows Installer encounters an error. Error code 0x80070646 and error code 646 are generated by Windows Installer,” the company revealed.

“These generic errors indicate that Windows Installer encountered a problem. When you encounter the errors that are described [above], the problem may be caused by an incorrect value in the registry.”

According to the Redmond company, Windows 7, Windows Vista and Windows XP users have all experienced and reported error codes such as those mentioned at the top of this article.

Fortunately enough, there’s an easy way to repair the issue. All that customers need is the Fix It solution designed to automatically deal with the source of the error messages.

The automated Fix It troubleshooter is available for download free of charge from Microsoft Support.

Microsoft also details the steps necessary for Windows 7 and Windows Vista users to manually resolve the problem. It all starts with firing up Regedit.exe:

“1. Locate and then click the following registry subkey:

HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders

2. In the details pane of Registry Editor, locate AppData. The value of this key should be %USERPROFILE%\AppData\Roaming.

3. If the value is not set to %USERPROFILE%\AppData\Roaming, right-click AppData in the details pane, and then click Modify.

4. Enter %USERPROFILE%\AppData\Roaming into the Value data box, and then click OK. Close Registry Editor.

5. Try to install the update again. If the problem persists, repeat these steps but use the following registry subkeys instead of the subkey that is specified in step 1:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders.”