I was upgrading my avg antivirus from 8.5 to the free 9.0 version. I was able to download and save this file to my desktop, but I could not install it due to Error: MSVC Redistributables installation failed. Installation of AVG can not continue. When I checked avg's forum they say this error is due to the fact that I do not have the 2005 version of the security update to microsoft visual c++. I had this problem before and I thought I fixed it. I do have the 2008 update. When I download this 2005 update it takes about 8 minutes and then the download manager stalls on 99% and then it says it is copying and then when I go to my desktop its not there. Now I can not download anything to my desktop. The manage opens and it acts like it is downloading but its not there. Checking windows update the reason for this 2005 security update failing to download is error 643. I've searched the internet but I can find nothing under this error code or in microsoft search. Can someone please help!