Unable to install avast 4 professional edition

This is a mess. On 10th January i purchased avast 4 professional edition. I downloaded it and double clicked on it. The avast message box came up and i clicked continue. It looked like it was installing - took about 10 seconds and only got as far as VPS and said it had finished so i clicked finish. My computer didnt restart and it hasn’t been installed. I tried a few more times but still it would not install. So I thought i had better install the free version as a only have a few days left with the free editon. which i think i have as now as later on when i tried to install the professional edition download the avast home edition installs instead. I’ve tried entering the registration key i got for the professional edition in the home edition it won’t accept it.

I’m at a complete loss. Can anyone please advise me how i can install the professional edition?

I’m also having problems with installing
Have you learned any more on how to resolve?

hello, make sure your comp is up to date with windows updates, try using the avast uninstaller “http://www.avast.com/uninstall-utility” to remove avast home edition, restart try installing avast 4.8 pro again and maybe “run as administrator” depending if you have admin privileges or not…hope it helps

I am having the same problem loading on to my new cp. can`t even get tec. support! I still have 3.5 yeats on my license.