Forums mIRC Help security problem and script editor!

If you reinstall mIRC, you're reinstalling the default scripts.
As mIRC scripts allow for a great many things, custom scripts (i.e. scripts made by you or other users) may be a security issue (...you have to either review the code yourself or trust a source/review). This does not apply to the default scripts (i.e. vanilla mIRC), even if you accidentally removed some part of it, as they don't contain "sensitive" commands.