Serial COM-connections 64bit versions

Question

I have a .net Application that writes text to a serial COM port, a POS reciept printer to be more exact. i am using the Rs232 class library to write and read to a serial device.

My problem is now with some clients that have updated their operatingsystem to WIN7 64bit version, have trouble to create a connection to the COM-port.

the com-port seemes to get occupied with some other process and that blocks my application to opening a new connection. so for my question, does anyone know how i can close all connections to a com port? or see whats blocking it? once again this seems to only to affect win7 and 64bit users.

thanks

Answer 1

You'll have to find the process that is hijacking the COM port. SysInternals' Handle utility should help you find it. Other than that, I've seen the Telephony service grab a COM port on one of my machines.