COM1 already occupied?

Solved
ecureuil64 Posted messages 6 Status Member -  
 locro -
Hello,
On PC NOTEX running XP, interfacing a GPS with a serial cable on the com1 port recommended by the application, a message appears stating that the com1 port is already occupied by another application. I don't have any other applications running apparently. How can I find out which one? Thanks for the help.

12 answers

henri59 Posted messages 3248 Status Member 1 256
 
Hi

It must be your modem occupying your COM1. To change the port, go to Control Panel, double click on Modem and Telephony options, click on Advanced settings, and at the bottom, click on the Advanced port settings button. In the dropdown menu for COM Port number, choose the port you want.

If you want to disable your modem, go to My Computer, right-click, Properties, Hardware button, Device Manager. Find your modem, highlight it, right-click, and click on Disable.
5
ecureuil64 Posted messages 6 Status Member
 
Thank you, Henri!
I did indeed disable the PCI modem (it was configured on com3)
I launch my application and I still get the message that com1 is already in use!
How can I find out which application is monopolizing it?
Thanks again for the answer to whoever holds it.
0
jmp59 Posted messages 29286 Registration date   Status Contributor Last intervention   6 349
 
Hello,

Do you have a low-speed modem?
(External or PCI card)

Bye.
2
Eldian
 
I found this response on a forum:

I'm digging up an old post, but it was Google that led me here and I've just encountered this annoying problem and solved it: it's Active Sync that occupies COM port number 3, which needs to be removed or reconfigured, an update of ActiveSync or the modem drivers might also do the trick ;)
2
ecureuil64 Posted messages 6 Status Member
 
If I do have a PCI modem. I thought I had disabled it? But how can I check?

Thank you
0
jmp59 Posted messages 29286 Registration date   Status Contributor Last intervention   6 349
 
Some ideas... since it's not your modem:

Some mice work on the Com port

At the back of the case, you should have 3 (or more) Com sockets. Check if one of them (the 1st!) is not being used by an external device.

Control Panel/System
In System Properties, select Communication Port (COM1), click on Properties.
In the General tab, check Disable in this hardware profile - OK.
And if what's "taking" this port is useful to you, you'll quickly find out what it is.
The indicated path applies to Win 9x and ME. For XP, it might be slightly different.

Finally, after all, using Com port 1 is only recommended. This means it might also work with Com 2. Have you tried?
0
ecureuil64 Posted messages 6 Status Member
 
Finally it works!
Thank you jmp59 for the last piece of information, indeed by disabling COM1 port and re-enabling it I have freed it up.
My application works.
Thanks to everyone and as a comeback. Well done CCM
0
erickv
 
Hello,

I have almost the same problem,
I have a modem for low speed and for some time now, when I want to connect, my computer tells me that the modem is already in use.
My modem is on port COM3 and in the device manager list, there is only port COM1 and LPT (for printer).
Moreover, when I want to change the port used by the modem, it tells me that (with any COM port) the ports are already in use as well...

What should I do?
Thank you in advance to everyone.
0
Sellos
 
I have the same problem. Can I delete ActiveSync? What is its purpose other than occupying COM3?
Thanks
0
cyril
 
I have a similar issue with Vista, what should I do?
0
cyril
 
Finally, I explain the problem:
I have a program (Ketron XPc) that needs a port to unload the music, but it shows me that my 4 ports are in use
Thank you in advance.
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jmp59 Posted messages 29286 Registration date   Status Contributor Last intervention   6 349
 
In the Device Manager, check if you have an internal 56K modem.
If so, since you probably never use it, disable it and it will free up the corresponding COM port.

--
To err is human, to persist is diabolical.
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renald06 Posted messages 3 Status Member
 
Check if you don't have the skeys file running in the task manager, if so, disable the serial key service and try again.
0
locro
 
Thank you for the solution.
I didn't get a "COM1 occupied" message but "Code 5 (Access denied)"
Switching the "SerialKeys" service to manual resolved the issue.
Thanks again.
0