Cant install Avast!4 Pro. properly

[that guy]

Hi,
I just purchased the 2 year deal for Avast!4 pro. I downloaded the set up so i opened it up and i get a window that gives me "Change", "Uninstall", "Update" and "Repair". So i hit change and went through the next steps. But when it starts to accually download, it stops and says "There was an error while changing the product configuration" and only leaves me a "finish" button. I tried to restart my computer but nothing happened. I would like to us the product i payed for, please help.

Thanks

[Tarq57]

Hi, welcome to the forum.
Generally it's been found (fairly often recently) that it can be better to download the full setup file from Avast, rather than the smaller file via Cnet. (The full setup file on that page is as pictured below.)

Were you using a trial or Home version of Avast before purchasing the pro? All that is needed (if so) is to insert the Pro licence key.

Were you using any other AV before Avast? (Important to remove.)

[that guy]

Well i recently got a new computer with Vista on it and it already came with it.

[Tarq57]

Sorry, I have no idea what you're saying, can you re-word that?
You mean that Avast was already on the new computer?
That doesn't sound right.

[.: L' arc :.]

Hi thatguy,

 It would be better to uninstall instead of overinstalling.

1   Download avast! Professional (English) here.
2   Disconnect from the internet and proceed to uninstall avast! Home
3   After the uninstall, restart your PC
4   Proceed to installing avast!
5   After installing, restart your PC
6   Right click a tray icon and select About avast!...
7   Click License key... and paste in your license key
8   Click OK

[that guy]

Where do i find my license key?

[Tarq57]

It would be helpful if you could answer the questions asked, particularly in regard to the AV installed on the computer before Avast.

I'm thinking that in your reply #2 what you mean is "Yes, there was an antivirus installed on my computer when I got it."

We need to know which antivirus it was.

Regarding your license key, when you purchased the Pro, an email should have been sent to the address you used. That contains the key, a sequence of numbers to be pasted into the appropriate place, after you have installed it successfully, which may depend on correctly removing the old AV.

[Lisandro]

I suggest an installation from the scratch:

1. Download the latest version of avast! Uninstall Utility and save it.
2. Download the latest avast! version and save it. Do not use the CNET option.
3. Uninstall avast from Control Panel (if possible). If, for any reason, you can't run it, try booting in Safe Mode and doing it from there. Anyway, boot after that.
4. Run the avast! Uninstall Utility saved on 1. If, for any reason, you can't run it, try booting in Safe Mode and doing it from there. Anyway, boot after you've run it.
5. Install avast! using the setup saved on 2. It will be good to accept the boot time scanning. Boot.
6. Insert the license key.
7. Check and post the results.

[that guy]

Ok i found the licence key and posted it and it was successful! Thanks guys!

[Tarq57]

Good one.
I'll just post this page that links to uninstallers for most AV's (with thanks to the original poster of that link).
You might want to grab the removal tool for whatever AV was last on the computer and run it.
After that, it may be necessary to repair Avast.