error 633 com port issues

Posted on 2006-11-10
Last Modified: 2013-12-27

I am having some difficulty with an internal modem, i am getting error633 and it tell me there is a conflict and that another device is using the port. I have tried to find my port settings in the device manager but the Ports (COM &LPT) bit is not listed so i can find out if its enabled

Has anyone got any suggestions

I am working on WinXP with SP2


Question by:socross
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LVL 97

Expert Comment

ID: 17914952
Greetings, socross !

Reinstall the modem driver. Go to Control Panel > System > Device Manager. Delete the modem driver. Restart the computer and let Windows reinstall the driver. Have the modem driver disk handy.

If no joy, with the computer turned off and power unplugged, move the modem card to another PCI slot. Restart the computer.

Best wishes!

Author Comment

ID: 17917946
Tried deleting the modem driver, restarting Windows and allowing it to re-install the driver. Unfortunately it made no difference.

The modem cannot be moved to another PCI slot as it is a laptop/notebook we are talking about here.

The modem is installed at COM3 and IRQ18. But all attempts to access the modem ( eg "Query Modem") just say that the selected port ( COM3) is already in use. How can I find what is already using that port ?


LVL 97

Expert Comment

ID: 17917972

Do you have another device using the Comm ports?  Disable it. And then try using the modem.
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Author Comment

ID: 17918927
There are no other devices using COM ports. I've tried assigning the modem to different COM ports but it makes no difference. Nothing I seem to try makes any difference and having trawled other EE threads on similar problems, I conclude that the the modem is faulty.

So I have reverted to an external USB modem, which had been causing some intermittent problems as well and which had been deleted to eliminate any conflicts with the internal modem. After a lenghthy trawl of the web, to find the correct USB modem driver (for a Mentor/Conexant EF56RII-USB/UK) this has been installed and all is now working fine.

In any case the client will be upgrading to boradband/ADSL soon, so all this will be history soon anyway.

Thanks for your input, war1.


To Page Editor: Can I award war1 100 points for suggestions, but not the full 500 points as the solution lay elsewhere.

LVL 97

Expert Comment

ID: 17919362

Glad the problem is solved. You can make a request to Moderator to make the change in the Community Support board.  The link in the upper right corner of this page.

Accepted Solution

Computer101 earned 0 total points
ID: 19518827
PAQed with points refunded (500)

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