Will not let me UNISTALL or UPDATE

i have the free version and my computer is a wreck because i let the security go on it. It all came down to when i tried to unistall the program it says …THERE WAS PRABLEM WHILE CHANGING THE RODUCT CONFIGURATION…so it will not allow me to unistall the program from my computer so i can downlaod another version…what do I do from here?? I have never had any probelms ever unistalling a program except this one…

Hi, welcome to the forum.
There isn’t really enough info of the type needed to make any kind of diagnosis, here, but there are some things of a general nature I can post which might help.
Plus some questions to narrow it down a bit.

Things.
-Download MBAM (a good demand scanner. Blue download button.) Install it, update it, run a quick scan. Get it to remove anything found. Post the log.

Run a disk cleanup. (Programs>accessories>tools.)

Questions:
-What is your operating system?
-What version of Avast Home have you been using?
-What AV (antivirus) was installed before Avast?
-What other security programs are installed?

  • Have there been any virus alert messages? If so, the virus names please, and the location/filename where they were originally found.
    -Any other strange behaviour? (redirects/popups/uncommanded scans etc).