ok, there are 3 things to prevent from being infected 1)update your windows version go to http://windowsupdate.microsoft.com ( or type in mIRC /run wupdmgr ) and click on product updates and download all the critical updates you need, and service pack 1 as well if not installed already. 2)get an antivirus, if you can't afford one, then try online scans like housecall the website for this online scan is http://housecall.trendmicro.com/housecall/start_corp.asp 3)Use common-sense... if someone sends you a file don't open it before scanning it dont go to porno sites and talk to ur friends about this and dont look XXX websites from irc spamers, or accept any files from strangers dont type any //write or $decode commands that ppl tell you in mIRC If you dont do that all, and you will be safe while on the internet and there's a big chance that you won't be infected.