Well, unless you have 2 computers you can't both use mIRC at the same time - you can both be logged on to IRC, but if you have one PC with one screen and one keyboard, you can't both type
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However, you can always open 2 mIRC clients. Just open one, and then click the icon again and it will open a second. I don't remember about other OSs but I know Windows XP has multiple user logins, and you can switch between accounts without closing other programs in the other account. Go to
Start > Control Panel > User Accounts.
Remember, if you both connect at the same time you will be connecting with the same hostname. Whilst 1 clone is not usually a bad thing and I don't know of any network that would /kill (disconnect you from the server) for it, if you both load individual bots you would have 3 clones and then you might be liable for a network ban (often called a G-Line or AKill). Some
channels will ban you automatically for just one clone.
Just a general FYI for IRC 'netiquette', most people won't call IRC
nicknames an s/n (screenname). S/Ns are usually left for MSN/AIM etc. There's a good IRC netiquette document
here.
Hope this helps..
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Regards,