Download error

apple

I use a laptop running Vista Home Premium.
Windows update is trying to and failing to download a certain update.
The update is: Security update for Microsoft.NET framework version 1.1 service pack 1 but each time it states it can't download due to error  643 can anyone help.

Regards Gordon                    
      

You are not alone with regard to Vista update problems most have fixed this by going to the Vista dowloads and downloading and manually install them                    
      

Thanks Algrange. Will try a manual download. Gordon