This is relating to Vista Home Premium on my Gateway desktop, I have been using Avast Free for a couple of years but decided to try AVG free which was my old favorite. I downloaded the installation file and then uninstalled Avast and installed AVG. That seemed to work fine and AVG ran OK but I still wasn't happy so decided to try Avira free. Went through the same steps to make the switch and got Avira running OK. I scanned with no adverse results. Shortly thereafter Firefox started generating ads on its own on webpages and occasionally opening new tabs with ad websites. I decided that I would go back to Avast and downloaded the installation file and uninstalled Avira After restarting the computer I tried to run the Avast installation program and got the error message "The installer cannot extract VPS files to 'C:\Users\John\AppData\Local....'. Trying to run the AVG installer yields 'Unable to extract the setup contents, Make sure you have administrator rights'. Running as administrator makes no difference. Running the Avira installation causes the computer to think but then does nothing (no message).
In the program list there is an entry for AVG 127 MB. If I try to uninstall I get a popup AVG Zen with the message 'We're sorry, but an unexpected error has stopped your installation'.
So effectively I have no antivirus for this computer which is the anchor for my home network. I intend to operate it in safe mode with networking and only use the browsers on my networked laptops which are working fine. So I will be responding to this forum via my laptop and transferring necessary files via a flash drive.
Would sincerely appreciate help in trying to restore my desktop to full function. TIA