I can not install AVG

Hello Wes,
We're sorry to hear that you're facing this issue while installing the AVG AntiVirus FREE program. 
We will certainly look into it and help you.
We request you to check for any necessary updates available in your Windows operating system. If yes, please update its convenient Rollup Update, uninstall other antivirus programs (if any), restart your computer and try the installation.

If the issue still persists, please try installing the service pack 2 on your windows 7 operating system and check the status. Keep us posted.
Thank you.

I have Windows7 Professional with Service Pack 1
When I attempt to install "avg_antivirus_free_setup.exe", I get this error:

"We are sorry but the installer must be run at high integrity level"

Why?

Hello Wes,
We're sorry to hear that you're facing this issue while installing the AVG AntiVirus FREE program. 
We will certainly look into it and help you.
We request you to check for any necessary updates available in your Windows operating system. If yes, please update its convenient Rollup Update, uninstall other antivirus programs (if any), restart your computer and try the installation.

If the issue still persists, please try installing the service pack 2 on your windows 7 operating system and check the status. Keep us posted.
Thank you.