Hello rmrkfr,
Please try to download full installation package and then follow all steps in AVG 2012 (incl. Previous Versions) Uninstall / Re-Install Instructions.
If you are still unable to install, provide us with installation log files.
Thank you
I am getting error code 0xc0070643, a general internal error and another error code of 26001. I am ok with computers but no real expert. I had the past version of AVG free and the first time it instructed me to download the new version, I was unable to. I really like AVG and would like to continue using it.

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