If your mIRC settings or your copy of mIRC are being deleted when you restart your computer, the most common reason for this is anti-virus software. Some anti-virus applications incorrectly think mIRC may be a trojan/virus and will delete it and or its settings when the computer is restarted. This is called a false positive. You would need to add mIRC to the exceptions list in your anti-virus software to prevent this. If that does not work, you would need to contact the anti-virus sofware developer to ask them for help.