Button.. mIRC has no 'button' that is for ignore.
Do you perhaps mean you right-click on the nick, it pops up a menu, you select 'Control' then 'ignore'? If so, you should see a line similar to '* Added *!*i73auth@75-161-97-137.albq.qwest.net to ignore list'. If you do, you need to copy/paste that line into this thread.
You should also do a '/whois <nickyouwanttoignore>', and paste the results of that too.
