Changing a legitimate Steam ID is against Valve's policy, and support staff will not assist in changing a permanent ID. For Server Owners: How to Stop Changers
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A Steam ID changer for Counter-Strike 1.6 is a tool used primarily in non-Steam (pirated) versions of the game to modify the unique identifier assigned to a player. In the original Steam version, your ID is hardcoded to your account, but in "No-Steam" versions, the game generates a "SteamID" based on hardware or software parameters. What is a Steam ID Changer? Changing a legitimate Steam ID is against Valve's