Pure Q3 client
In Quake 3 folder you must have only this:

• baseq3\pak0.pk3
• baseq3\pak0.pk3
• baseq3\pak1.pk3
• baseq3\pak2.pk3
• baseq3\pak3.pk3
• baseq3\pak4.pk3
• baseq3\pak5.pk3
• baseq3\pak6.pk3
• baseq3\pak7.pk3
• baseq3\pak8.pk3
• baseq3\q3config.cfg
• q3key

Nothing else cant be there :!: How pure works : Why pure :

• Pure Q3 server check checksum for each pak file and if one of files have wrrong checksum you will be kicked with apropriate message also check lenght of file, file must match in single byte of length.
• What is the checksum :
• Checksum is generated by unique programm algorithm which generate for each file unique code which is maked by scanning whole file.
• Also if you have any more files or less files then have to be you will be also kicked :!: What is the meaning of pure server, why pure server :
• Because chating can be acomplished with modifying pak files like wallhacking etc. Or player with unpure pak files can have "unfair advantage" I quote that because IMO that is also cheating. How low explosions work :
• When somebody shot at you you then have lower exposions and you see away better your enemy, then you can easely point at him and kill him.
• Unpure pak files you can have if you download them, thats mean you cant have it by accident, or you can modify pak files by your own (rear cases, comprehensive users) :!:
• Also you have to disable autodownload swich and on that way forbide to your Q3 client download into baseq folder. After while you have to check your baseq folder. And if you find anything what dont belong in baseq delete.
• New maps download manualy from server that maps are with ZIP extensions. When You download map, just rename extension ZIP with pk3 extension and put that file in EXCESSIVEPLUS folder.
• Pure is maded by ID Software to preserve unpure pak files.

Also I notice organizing E+ World Cup Of Nations that alot people known well in comunity was have alot problems with purity of clients, and that is verry sad. Fortunatly I did not see anyone who have wallhack or etc. Some serious shit. In that case I will report it on forum. Fortunatly I havent such a case. I help those people to pure their clients. So, my recomandation is play CWs with PB ON and PURE ON, ONLY :!:
If You wanna play failrly and not be cheated by anyone and wanna play TDM you use TDM server it is always PB ON and PURE ON, also you can check your purity there. I notice also that some people havent pak7.pk3 and pak8.pk3 and server kick them after while not emidiate kick. So, I send to them those files and they now can play as pure.
Regards people, be PURE :!:

Punk Buster :!:
What is PunkBusterTM : PunkBusterTM is service which prevents to use other cheats which cannot be forbiden with pure Q3 server. :!: Initialy ID SoftwareTM produce Quake3 with Punk Buster client. Also ID Software make switch Pure Client ON and OFF. Also PB client on and OFF. Meaning of punk Buster service is to handle other cheats which canot be handled with pure server like I said. So, you have to update your PB client on regular bases. Also server owners have to watch any progress on http://www.evenbalance.com and make apropriate changes on Server side PB and PB cfgs. PB is service which can find on client any known cheat codes which are in DLL files which are linked usualy from q3 cfg file, not neceserily. Most common known cheats are autoaim, autoshot or both. Alot other cheatcodes which are not so eclatant as so called "Aimbots" exists. With PunkBuster TM server admins can ban people with CD key which are unique GUID="Global Unique Indentifier" so every use on client side have UNIQUE number wich represent him. Some extreme abuser can be in theory globaly baned on all Q3 servers.
How install or update PunkBuster client side read here :!:

Myth
I also must wrote here one myth. Usualy AnttiPunkBuster people say that PunkBuster ON on server make lags. Lags ocured only on servers which havent good bandwith or servers which havent enough processor power, but ONLY IN CASE WHEN SOMONE NEW CONNECT. Then PB service scan client. And even in that case when server have lack of processor power or bandwith or both I am for that little lag reather then somone cheat on me.

IF YOU WANNA PREVENT CHEATING WITHOUT 0-24 WATCHING SERVERS, MAKE THEM PunkBusterTM WELL CONFIGURED AND UPDATED, ALSO MAKE THEM PURE. ONLY THAT CONFIG WITH REGULARY UPDATED SERVER PB SIDE GARANTEE FAIR PLAY TO ALL ON PARTICULAR SERVER :!: PUNKBUSTER ON WITHOUT PURE SERVER ON HAVENT ANNY SENCE :!:

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