Ports not listed in Device Manager

  Jim Thing 21:31 27 Nov 2007

I need to check (and possibly change) a COM port setting on my laptop (Acer Aspire 7003WSMi, running Windows XP Home + SP2), but Control Panel > System > Hardware > Device Manager doesn't list any ports at all as far as I can see.

All suggestions gratefully received.

  DieSse 00:12 28 Nov 2007

Well it certainly should show any working external com ports. It may not show and "virtual" comports such as those emulated in Win-modems - I seem to remember it does, but I can't check as I don't have a modem.

I presume you do have at least one externally accessible com port on your system?

You should look in the BIOS to check whether it's shown there as active, and not disabled.

What is it you wish to change? - it's an uncommon requirement to need to change com port settings.

  Jim Thing 10:33 28 Nov 2007

Thanks for responding. I want to install a software update for my Humax PVR. The instructions on the Humax support website tell me to check that the COM 1 port is set to 115200bps — but I can't find the Ports(COM & LPT) item is missing from the Device Manager list.

The BIOS on this laptop seems to cover much less territory than its counterpart on my desktop, and I can't find anything about active/disabled ports in it — but I have to confess that I'm out of my depth when it comes to messing about with the BIOS.

  Jim Thing 10:43 28 Nov 2007

The last sentence in my 10:33 post should have read "...but I can't find the Ports (COM & LPT) item because it's missing from the Device Manager list."

Sorry! (It's me age y'know...)

  HCOOH 10:44 28 Nov 2007

Found this article
click here

  Jim Thing 11:21 28 Nov 2007

Thanks for the link. I'll check it out and report back.

  Jim Thing 12:27 28 Nov 2007


  DieSse 12:29 28 Nov 2007

COM ports are normally at 115Kbps or higher.

If your software isn't working it's probably because the com port doesn't appear in Device Manager.

When in Device Manager select View - Show hidden devices - and see if anything appears that might shed some light on things.

  Jim Thing 19:44 28 Nov 2007

Thanks to HCOOH's link I've found an item called Serial, listed under 'Non-Plug and Play Drivers' in Device Manager, that has a yellow exclamation mark alongside it. Now I guess I need to discover why it's flagged and how to fix it.

At the moment I'm fighting a losing battle against Acer's online Users' Guide, which seems to bear little relation to what appears on the screen. Couple that with my own shameful ignorance and you can see that I'm still in grave need of expert advice.

I think I should have posted this in Absolute Beginners.

  HCOOH 21:07 28 Nov 2007

I think serial.sys is one of the COM1 drivers. Can you do a search for serial.sys and see what happens.
Should be in system32 drivers.
Might be barking up the wrong tree but can't think of anything better.

  Jim Thing 21:32 28 Nov 2007

Aye, serial.sys is indeed in WINDOWS/system32/drivers. Could it be corrupted perhaps? If so, how can I replace it?

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