Hi
I bought a new avast pro eddition today and can’t install it on my computer. I have a old version of avast 4.8 and it’s to old so I dont have any protection for my computer. I need help.
Downloaded the program from the website and when I tried to install it it didn’t work, only said error… ???
what should I do?
please responde here
Hi gullmakDavid, welcome to the forum 
First, please use the modify button on the top of your post, and remove your email address. This is not necessary and will lead to you being spammed…
If you already have a copy of avast! home installed, you should be able to enter the registration number that you received for the pro version, and it will unlock the features of the pro version.
What version of avast! do you already have installed?
Did you have any other antivirus before avast? which was it? how was it uninstalled?
-Scott-
withdrawned my mail, thanks
well avast home 4.8 antivirus protection.
I cant find a place to whrite the licencekey in my old program ???
You still haven’t withdrawn your email from your actual post above. near the top right of it, there are two buttons, quote and modify. Use the modify one and take the email address off. If you wish to be notified of posts by email, you can press the notify button at the top of the thread.
To enter the license key:
right click avast! tray icon → about avast → in the bottom of the window that opens, there is a button that says license key → click it and copy and paste the key into it.
There is also a tutorial if needed:
avast! license key tutorial
What was the error message you got?