Originally Posted by ZIDANE

It most likely came with another piece of software or something you have downloaded/accepted recently. If you cannot remember then try doing a search in you're program files for 'mirar' it may bring up a directory with the uninstall files or the actual program it came with.

If all the above fail I'd suggest you run a virus check or spyware check. (search for Spybot in google if you don't have a spyware checker)

This will most likely bring up the infected files and remove them for you.