Hark is a simple Word Macro virus. Infected documents have macros called "AutoOpen" and "Harkone".
This virus has an interesting activation routine. On 1st of June the virus maximizes all active windows, changes the font size to 60 and insert the test "HARKONE" and "NJ [SLAM]".
SLAM is a name of a virus-writing group.
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.
Technical Details:Katrin Tocheva, F-Secure