atcomsystems.ca/forum Forums Computers & Programming Computers, Software, Accessories Changing com ports in a file

Hi everyone. We have a laptop computer that has a bad com port 1. We have a file that defaults to com 1 and we need to change it to default to com 6. Does anyone have the steps to do this through start, run cmd? Any help would be greatly appreciated. We have tried everything and it is not working. Thanks.

I assume you are running Windoes. If you have tried everything and it is not working, then it is logical that nothing will work.

However you may want to go into the Device Manager and disable your existing COM ports except the one you want to use. That one should be uninstalled in the Device Manager. Now reboot and go into your BIOS setup and disable all the serial ports there except the one you want to be COM1. When Windoes restarts it should setup the only port that that has not been disabled as COM1.

Also keep in mind that a modem contains a serial port, so you must disable all modems too.

I don't think you need to go through all that. Device Manager will let you assign what Comm Device uses what port.

My PC> Properties> Hardware> Device Mgr> Ports> Select Com Device> Port settings> Advance.

There you will find where to change the com assignment.

That's too easy.

Still, if COM1 is in use by another device, you need to free it up first before assigning it to another device, or you may develop a conflict.

You might try this

https://support.microsoft.com/kb/819036

There is an old DOS command that will show you the status of all your ports at once. This is MODE.

In Windoes, click on Start, click Run, type CMD and press Enter. In the command line interpreter that opens up, type MODE and press Enter. You will see a list of all your active ports and their settings.

Here is an example:

C:\Documents and Settings\user>mode

Status for device COM1:
-----------------------
Baud: 1200
Parity: None
Data Bits: 7
Stop Bits: 1
Timeout: OFF
XON/XOFF: OFF
CTS handshaking: OFF
DSR handshaking: OFF
DSR sensitivity: OFF
DTR circuit: ON
RTS circuit: ON


Status for device COM3:
-----------------------
Baud: 115200
Parity: None
Data Bits: 8
Stop Bits: 1
Timeout: OFF
XON/XOFF: OFF
CTS handshaking: OFF
DSR handshaking: OFF
DSR sensitivity: OFF
DTR circuit: ON
RTS circuit: ON


Status for device CON:
----------------------
Lines: 999
Columns: 250
Keyboard rate: 31
Keyboard delay: 1
Code page: 437

You can get some of the same information in Device Manager but only by clicking back and forth in a lot of different places. The MODE command gives you a nice, quick summary.