Why Flash Speed 200% appears as virus for AVG anti-virus?

I downloaded the exe. file for installation of flash speed, once the download completed, the AVG identify it as virus, how can this be??

Why Flash Speed 200% appears as virus for AVG anti-virus?hp

Because there's a string of bytes in it that's the same as a string of bytes in a virus AVG knows about. That's how anti-virus programs recognize viruses.