Generally, it's recommended to have only one running. So if you're happy with Vipre, uninstall Avast.
Is it OK to have 2 antivirus programs installed? I was instructed to download CCleaner before fixing a problem on my computer. I did not realize the Free Avast downloaded with it. I previously used Free Avast but now use Lifetime Vipre which automatically upgrades without additional cost.

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