I have recently registered my channel and was an operator of my own channel, after being talked through what to do in order to become registered.

But somehow I have been removed as an operator of my own channel, but shows users who have not been selected as op`s are op`s. How do I reset myself as an operator of my own chatroom. I was told what to do by typing something with my username logging in and out very quick, but I have already forgotton how to do this.
Can someone please help.

A founder cannot be 'removed' unless it is done by the server's administrator or someone got hold of your password. Assuming that your channel service is ChanServ you will type /cs info #YourChannelName or /msg ChanServ info #YourChannelName and int he notices that follow it will tell you if you are still the founder or not.

See how you go.

If it is still your nick then just try to identify to the channel. Always use Status Window to issue authentication commands. Make sure the Caps Lock is off too.

Follow Watchdog's advice, but in addition realize that networks and their services vary. While we can offer advice, for the most accurate advice, check with #help or #mIRC on your own network.