Maybe it's because you hacked or you edited vital game files??

Valve Anti Cheat System
I've Been Banned

The VAC system reliably detects cheats using their cheat signatures. Any third-party modification to a game designed to give one player an advantage over another is classified as a cheat or hack and will trigger a VAC ban. This includes modifications to a game's core executable files and dynamic link libraries.

Use only trusted machines to play on VAC-Secured servers - if you are not sure whether or not the machine you are using to connect to Steam may have cheats installed, do not play on VAC-Secured servers.

Use caution when installing any game modifications, such as scripts or custom skins. Only download custom content from trusted sources. Hackers sometimes maliciously disguise their cheats to cause others to get banned.

And the fact that a good 1/3 of your friends are also vac banned is mere coincidence?

And you were vac banned in May. So may we assume that one was also fake too?

Vac appears to be working fine. Your "undetected" cheat, not so much

Originally posted by Satoru:

And the fact that a good 1/3 of your friends are also vac banned is mere coincidence?

And you were vac banned in May. So may we assume that one was also fake too?

Vac appears to be working fine. Your "undetected" cheat, not so much

Let's not forget the Anti-Vac group he is part of.

Originally posted by ゆき:

Originally posted by Satoru:

And the fact that a good 1/3 of your friends are also vac banned is mere coincidence?

And you were vac banned in May. So may we assume that one was also fake too?

Vac appears to be working fine. Your "undetected" cheat, not so much

Let's not forget the Anti-Vac group he is part of.

In his defense it appears little more than a vac whiners group rather than some kind of hacking group for vac. But their video is pretty laughable as "proof" of false vac bans

Hi i readed all comments and my answers to all of them is DA ♥♥♥ O_o
i have ALWAYS been a NO HACKER (Never hacked)
And NO ive never edited an game.... only addons for garry's mod and thats ALL

If you are absolutely telling the truth about only ever having perfectly legit addons for Garry's Mod only, has anyone else had access to your account?

If so, they may well have cheated on your account.

GMod is vac enabled so if you cheated there you will be vac banned

Like I said why are 1/3 o your friends vac banned

Why were you vac banned in may?

STOP CHEATING

Don't shoot him down so quickly, I love these threads.

Yes, I'm sure you can surely re-code VAC yourself, OP.
You must be a major in computer software, no?

Oh wait. You're not.
And don't let others put cheats on your account.
In fact, stop cheating altogether.

I LIKE TURTLES

Originally posted by Mathias.DK^5The ^6Pro:

My account got banned for NOTHING ive NEVER hacekd and never gonna... hack is for losers...

You're a filthy cheater and you've gotten caught.

One way to solve this is to open-source the VAC rules engine entries (and maybe not neccesarily the raw source code). Of course people would find loopholes, but then more honerable people would make suggestions on how to plug them. In the end the community would be the quickest way to validate that VAC is always right and never has false positives, while destorying any fool that would try to violate it.
Contingent on Valve letting us mere mortals know anything about VAC that they haven't already vaguely stated.

The problem isn't with the closed source nature, its the fact that AC software fundamentally runs in an insecure hostile environment, which is the opposite of how anti-virus softwaare operates. You're basically telling a piece of software to try and detect something, when the attacker OWNS EVERYTHING ON THE SYSTEM. In the AV world you'd just nuke the box if such a virus was on your system. In AC you're asking it to detect something on an already compromised system which inherently means you're not going to find everything.

VAC doesn't ban for nothing. It found something. If you wanna contest your ban contact Support but they will most likely just confirm the ban.