You get a message that updates are available for your computer. You tried to add them and got a message "Windows Update encountered an error. Code 643 and 646". You are also getting messages that a script has stopped working when you go to new websites.
What can you do?
Please download and run a Microsoft patch registration cleanup tool. Click a "PatchRegCleanup-x86.exe" download button on this page to start a download. To start an installation immediately, click "Run".
To save a download to your computer for installation from your desktop, click "Save". Double click on "PatchRegCleanup-x86.exe" to run it. You may need to enter your Windows Vista product ID.
You can try it again with a correct code. To find your Vista product ID check your paperwork, any CD/DVD that came with your system, look on back or bottom of your computer. Also, you can look for it in control panel.
Click your "Start" button then select "Control Panel", "Classic", and then "System". On bottom of window Product ID is listed, which might take a minute or two before it shows up. You can try this, go to "Control Panel" then select "Windows Updates".
For each update that will not install, click "Important Updates", or an "Update" itself. Double click one then click "View More Information", or click on it then "View" on right side. Those will take you to a page where you can download an update.
You can go to Microsoft Download Center and put in a KBxxxxxx number to download it. Click on "Download" then "Save". Browse to where you saved a KB then right click on it and select "Run as administrator".
Then you can right click on an update in Windows updates and choose "Hide". If you get an installer error install Windows installer 4.5 redistributable. I think that one or more updates might be causing your problem.
I suggest trying to manually install them one at a time. Hopefully, they will all install successfully manually so that Windows updates begins automatically installing them again. If you have problems with one of those updates then you can narrow it down to that specific one and troubleshoot from there.
Also, a problematic update could be causing Windows automatic updates to completely fail.
About Author Aaron J. Berg
Aaron J. Berg is the owner of Anet Computers, host of the Reality PC podcast, and blogger at AnetComputers.com. For over thirteen years, he worked for fortune 500 companies and the United States Federal government supporting computers. Now he helps you solve your most common computer problems.