Valve released a new version of their VAC (Valve Anti-Cheat) today, including their new wallhack blocking code. If your server uses HLGuard and has wallhack blocking enabled, make sure you turn it off so Valve's can work properly!
I have never touched the HLG configs on the S4C server and have no idea where to begin! Any help in this respect greatly appreciated.
Also, on a related topic, what needs to happen to upgrade to HLG 1.30?