Something Busies COM1 port , but what, how can i determine it???

Whenever i start/restart windows. I see that sth opens and closes the port COM1. I use Hyperterminal to determine this. I tried several tools to see which program/handle sends windows messages to open/close the COM1, but i don't see any message. Another program shows the status of the serial ports shows that the COM1 is getting opened and closed continuously. How can i determine what deals with the COM1 port???

Thanks for further help,

Semih

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