/SLASHPLAY
How to unban an IP in CS:S
Type removeip 203.0.113.50 in the server console to lift that IP ban, then writeip to save the change.
removeip
Removes an IP address ban.
removeip <ip> Examples
removeip 203.0.113.50 Unban an IP.
Arguments
ipRequired- IP to unban.
What it does
Run writeip afterwards to save it.
The game's own description: Remove an IP address from the ban list.
Run it on your server
On a SLASHPLAY server, type it in the Console tab of the server page; the reply shows right under it. A value set there lasts until the server restarts. To keep it, add the line to cstrike/cfg/server.cfg. New to this? Start a CS:S server first.
Your own
CS:S server.
From $0.03 an hour, only while it runs. New accounts get 6 free tokens.