No it's not. Elysium had it first.
I use AC all the time and i've had it installed forever, presently I have anticheat.dll in my folder like most players ( i even downloaded it again and overwrote it over the old file), i updated it a zillion times and it still says I'm not usig anticheat when I join tastyspleen servers (auto-kicks me from T4, on t4-noalias it lets me join but says im not using AC). And no, I havent played with my settings or files, it just happened 1 day, last night i played and now this. Makes no sense. What is the reason of this?
Solution 2: For Windows Vista Service Pack 1 and later, Windows Server 2008 and ESET security product version 4.2.x or later The Windows Filtering Platform (WFP) is new with Windows Vista Service Pack 1 and later and with Windows Server 2008. The WFP architecture is used to check network communication and since it uses special monitoring techniques, the Web browsers section is not available. To exclude applications from protocol filtering on these systems with an ESET security product version 4.2.x or later installed, follow the steps below: From the Advanced Setup tree, click Antivirus and antispyware Protocol filtering Excluded applications. If the application you wish to exclude is listed, click the corresponding check box to select the application. Click OK to save changes.
From the FAQ on your AVs siteCode: [Select]Solution 2: For Windows Vista Service Pack 1 and later, Windows Server 2008 and ESET security product version 4.2.x or later The Windows Filtering Platform (WFP) is new with Windows Vista Service Pack 1 and later and with Windows Server 2008. The WFP architecture is used to check network communication and since it uses special monitoring techniques, the Web browsers section is not available. To exclude applications from protocol filtering on these systems with an ESET security product version 4.2.x or later installed, follow the steps below: From the Advanced Setup tree, click Antivirus and antispyware Protocol filtering Excluded applications. If the application you wish to exclude is listed, click the corresponding check box to select the application. Click OK to save changes.Have you tried this second part to the process? It looks like it might be blocking the network traffic that anticheat is using to communicate. Let us know if it works so this solution can be added to the anticheat AV help thread.