the real problem is mIRC wont let you stop the channel list (in v5.91 anyway)
Quote:

Get List
This retrieves a list of all of the active channels from the IRC server. This list can be quite long and depending on your connection it might take several minutes to download. The IRC Server actually sends the whole list, regardless of the filters you specify. You will not be able to do anything on IRC until this retrieval has been completed.