I just downloaded latest update of Avast. Opened Firefox and within 1 minute it froze. I rebooted and then couldn’t even access Windows XP - it just wouldn’t open when I tried to click on my name and password. Have rebooted many times and nothing. Please help. Linux is also on this computer hence I’m able to work with that, but I need access to my Word files. Many thanks.
Welcome to the forums, maryw. 
Have you tried to restart in Safe mode?
What OS does your computer have?
What was the former av program and how was it removed?
What other computer security programs are on your computer?
Hi and thanks. I’m using Windows XP and Linux. When it boots it gives me the choice to use either operating system. The Avast was just a “click on this icon to update”. I think it’s just Avast I use as anti-virus software because I want to avoid conflicts. A friend set up the computer for us; my husband and I have separate log-ons and it is this log-on button that doesn’t work, it also won’t turn off when I click the button? How do I restart in Safe mode? Sorry talking to a novice here… ??? :
I am not that familiar with duel boot systems, but, the normal procedure to start XP in safe mode is to repeatedly press F8 just after pressing the Start button on your computer. In your case, I suppose you would do this just after selecting XP as the OS. Perhaps one of the regulars on here with duel boot systems can confirm this?
maryw, choose Windows to boot and keep pressed the F8 key while clicking enter… the option for Safe Mode should appear.
Thanks, Tech.
I think the chances are high that there is another AV installed on the system.
You can’t use one on one account, and another on a different account, on the same OS.
You are probably right, Tarq, and that was what I was going to get Mary to look for if she can get into Safe mode.