I’ve been reading about alot of the problems with the new 5.0 version of advast (the free one) and haven’t installed it yet. Have many of you put off installing this new version.
if you experience problems, you can always report them here and people will help you 
Only advice I can give if you want to give it a try is to uninstall first avast 4 completely using this: http://www.avast.com/uninstall-utility , then reboot, install avast 5 and reboot again. Do not attempt a direct upgrade, even if it worked for some, it’s been a disaster for others. So if from the beginning you get a very clean install, chances are it will work well on your system.
Take one extra step:
Uninstall avast! 4 using the Add/Remove module, reboot, use the removal tool mentioned by Logos, reboot again and then install avast! 5.
Big problem.
Uninstalled 4.8 as per this tread.
Downloaded 5 - appeared in install but nothing happened
Did system restore and avast! icon appeared with red circle in it.
Tried starting frpm avast icon - failed
Tried add/remove - unable
Tried re-installing 4.8 - download failed.
Tried Revo uninstaller -failed.
Am running xpsp3.
Help
Did you uninstall avast 4.8 with the uninstall utility ?
What other security software are you running besides Avast? Did you go to a system restore point well before you updated Avast?
Couple of things to try:
Go to safe mode and uninstall Avast! from there using the uninstall tool discussed in http://www.avast.com/uninstall-utility
Reinstall 4.8 or 5.0 over the top of whatever failed installation you do have, which may help you uninstall the result
Thanks for replies.
Yes unistalled 4.8 as per recommendations.
Security software Online Armor firewall/Superantispyware Pro/Win patrol free
I was in the same boat with reading all the negative posts with others having trouble. This morning, I took the bull by the horns and I used the same procedure as bob3160 just mentioned. Sure, it was not easy for me as I haven’t used Safe Mode probably in 6-7 years and had to read up and view a tutorial to use it to run the removal tool. The positive to all that is with a clean install for a brand new version I didn’t have any trouble. I’ve been reading posts here for a week and trying to make up my mind on what to do as I appreciate Avast AV very much. I have the Avast Free version and run it alongside Online Armor Free firewall for a great combination. I did delete all past Online Armor permissions in use for version 4.8 so new permissions would be acquired once I connected to the Internet with Avast to get new updates and to register. Follow Bob’s advise (clean install) and you should not have any trouble. (I have Windows XP SP 3 in use.) I did remove Avast 4.8 via Add/Remove programs prior to using the removal tool and thought it was not removing anything else and sure enough, it found stuff left over from v 4.8
Me i did uninstall it in normal mode with removal tool and so far no problem so i hope another user could help you. Just be patient im sure there will be some 1 that know your problem.
Tried Safe Mode option - would not let me remove 
But why, e.g. what errors were displayed ?
If it was blocked by the avast self-defence module, then you werent in safe mode as avast doesn’t run in safe mode.
DavidR
Took it out of self defense mode before starting Safe Mode.
In Safe Mode went to Add/Remove it appeared to ignore me but when rebooted on normal mode avast! had disappeared. So downloaded 5 again and tried to install.
At end of installation said installed with errors (or words to that effect)and to reboot.
Did this but still had not installed said unable to find skin!! Not sure what that had to do with price of eggs ! 
I’m stumped!
Did you try the removal tool mentioned above from safe mode to try and remove all traces of a problem installation? Then try reinstalling 5.0 in normal mode?
Yes I did
Just to clarify something,I did install the new version on two laptops,one with XP and the other running Vista,did not uninstall previous version of Advast,and both seem to be running fine,I don’t know if I was lucky or what by not uninstalling the old version but it does say you don’t “have” too. My concern was installing it on my desk top which we use everyday. Just curious,there will come a time when the older version is no longer supported,isn’t that correct.
Avast 5 is designed to install over 4.8 while removing 4.8 during the install.
There should be no reason to first uninstall 4.8 in normal cases.
An incomplete uninstall of 4.8 will many times cause problems when trying to install avast 5.
I have now done this a total of 7 times with both avast 5 Free and avast Pro 5 without any problems.
Thanks Charley,I’m going to probably install it on my desk top in a few more days,will let everyone know how I make out,it seems some people are having no problems while others have several issues,I’m a novice when it comes to computer problems so thats why I’m always hesitate to install a newer version of a program that works just fine.