But if you can't send and receive some data you won't know if the device is still there :-(

>the port is closed because of a network failure. Lost packets for example.
>I have a wireless device that has a serial comm port.
>>I don't know. But even Scanners must have diagnostic commands. I don't know the logic of your application, and why you want to close the COM, why you not just leave it open?
>>
>>>What do you mean by "send"?
>>>I have a scanner attached to the comm port. Can I send data to it?
>>>>>it would be too easy.
>>>>>MSCOMMControlInstance.PortOpen keeps true value even if you power the device with a comm port down.
>>>>>
>>>>>
>>>>>>>>>Does anyone know if it's possible to regularly check a comm port whether it it is still open? I tried to open a port in the form, then disconnect the device that has a comm port but the form still thinks that the port is open.
>>>>>>>>>Thanks for any idea.
>>>>>>>>
>>>>>>>>How you open and close COM?
>>>>>>>I am using mscomm activex control.
>>>>>>

>>>>>>IF MSCOMMControlInstance.PortOpen && Port is opened
>>>>>>   do whatever you want to do when the port is poened
>>>>>>ENDIF
>>>>>>
>>>>>>***
>>>>>>MSCOMMControlInstance.PortOpen = .f. && Close Port
>>>>>>

>>>>
>>>>This is true. Just try to send some test command to device and see if you'll get the answer. If you don't receive any answer then close the COM.