This is a simple virus with an uncommon activation routine: on some machines, it turns the the BIOS boot-up password on and changes the password to 'monica'.
Do not confuse this virus with Monika.686, which is a totally different virus.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
More information on scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.
Description Details: Mikko Hypponen, F-Secure