What
other security software do you
currently have or did you have
in the past on this machine including:
- Antivirus (AV)
- Firewall (FW)
- Trial versions of AV, FW and other security programs
- Other security software
How did you remove/uninstall the previous security software? Vendor's uninstaller tool or some other way?
Since you mention that you are trying to install Avast 5, I am assuming you mean the latest version of 5.1.889 and not 5.0 (last version being 5.0.677).
You can first try an
Avast Repair:
- Go to Control Panel > Add/Remove programs > Avast Antivirus.
- Scroll down and choose Repair function in the pop-up window.
- Reboot.
If the Avast Repair fails to fix your problem, then I suggest an Avast
uninstall and clean install:
1. Save a copy of newest version of Avast 5.0.889 and save it to your HDD:
Free:
http://files.avast.com/iavs5x/setup_av_free.exe2. Download the Avast Uninstall Utility
http://www.avast.com/uninstall-utility and save it to your HDD (it has uninstall tools for
all Avast versions and products).
3. Disconnect from the Internet at this time.
4. Go to Control Panel and uninstall Avast through Add/Remove Programs if possible and reboot.
5. If Step 4 fails, boot into
Safe Mode (hit F8 repeatedly) and run the Avast Uninstall Tool.
You will need to uninstall version 4.0, 5.0 (if you installed it), and 5.1 (if you installed it) at this time.
6.
Reboot.
7. Install the newest version of Avast and
reboot.
8. Get Internet access and register your copy or add the license key for Free, Pro, or AIS.
Free –
http://www.avast.com/registration-free-antivirus.php9. Update the Avast definitions.
Please let us know how this works for you and let me know what other security programs you have installed on your machines (first question). Thank you.