I have a similar problem. I tried to upgrade from 8.5 to 9 and the installation failed at the last hurdle with the following message.
"MSVC Redistributables installation" error
Hi All,
I dont think its AVG at all, i have the paid version and got the same issues, but this was after i updated to the latest version of Firefox.
Often when going into Firefox the home page seems to be trying to look for an AVG page - at the bottom it says something like 'searching for AVG.com' then pauses for a minute, then I get the standard yellow error page from Firefox: "domain not found, did you type ww.mozilla instead of www.mozilla" etc
Then sometimes (like now) Google opens no problem.
I'll maybe try updating too MANTO and see what happens - although autoupdates are 'on' so it shouldn't be an issue.
However, I googled the problem a few days ago (there isn't a lot on it) but a few sites seem to suggest an older MS update (that may have previously failed) may correct this.
Something MS....frame...NET etc etc??
Or Firefox...