COM Port 3 has become unavailable

[Guest]

I use Laplink 12 under Windows XP to connect two computers with a serial
cable. Laplink has been using COM 3. Now, Laplink tells me that the port is
"unavailable." Using the Laplink option to try to configure and enable the
port does not work. A portion of the "configure" dialog/setup box is
greyed-out.

My other COM ports are also unavailable. Device Manager shows only COM 1.

How can I renable a COM port, probably COM 3, so that Laplink can again use
it? I will appreciate advise.

 

[Guest]

Hi Robert
I don’t know if I am talking about the same problem, but something similar
is happening to me just with XP connected to an scale.
To reactivate we discover to ways:
3. Turn off the PC, disconnect the RS232 cable turn it on again and the
reconnect the cable again.
4. Uninstall the serial port and install it again

Both of this solutions are not practical and I still looking for a better one.
I would appreciate if you know something new to let me about it.