COM ports not available

[Affan]

Hello everyone,
The COM port on my Dell 600m Laptop, donot seem to be accesible for
some reason. Although the device manager shows there are no conflicts,
and that all is clear and functional, if I do go to command line and
type > MODE COM1 I get the following:

MODE COM1

Device COM1 is not currently available.


While COM3 (for my modem) is working perfectly!!!
Any Idea what the problem is?
Help would be much appreciated.

Regards
Affan

 

[Vagabond Software]

Hello everyone,
The COM port on my Dell 600m Laptop, donot seem to be accesible for
some reason. Although the device manager shows there are no conflicts,
and that all is clear and functional, if I do go to command line and
type > MODE COM1 I get the following:
Device COM1 is not currently available.


While COM3 (for my modem) is working perfectly!!!
Any Idea what the problem is?
Help would be much appreciated.

COM1 and COM3 share the same IRQ (IRQ 4). Back in the old days when the mouse was a serial device, people would commonly run into this conflict between their mouse and their modem. After the mouse became a PS2 device, people started plugging PDA sync cradles into COM1, sustaining the aggravation of IRQ sharing (or lack thereof).

I suspect that is what you are seeing.

carl

 

[R. McCarty]

Since modems generally use COM3, change your Motherboard
Serial Port A to be COM2, using IRQ #3. If the MB has a Serial
Port B, set it's mode to disabled.

Hello everyone,
The COM port on my Dell 600m Laptop, donot seem to be accesible for
some reason. Although the device manager shows there are no conflicts,
and that all is clear and functional, if I do go to command line and
type > MODE COM1 I get the following:
Device COM1 is not currently available.


While COM3 (for my modem) is working perfectly!!!
Any Idea what the problem is?
Help would be much appreciated.

COM1 and COM3 share the same IRQ (IRQ 4). Back in the old days when the
mouse was a serial device, people would commonly run into this conflict
between their mouse and their modem. After the mouse became a PS2 device,
people started plugging PDA sync cradles into COM1, sustaining the
aggravation of IRQ sharing (or lack thereof).

I suspect that is what you are seeing.

carl

 

[Affan]

I looked it up.. my modem is using COM5. I still changed the IRQ of the
COM1 serial port to IRQ3 but still the same error msg that i get if I
do MODE COM1.

Just as additional info. I have installed also (in addition to the
standard serial port my laptop has) a USB to serial converter. This
worked fine on my old laptop (i.e. i didnt need to change any IRQ or
hardware settings) but now even though the device manager shows it as
COM5 i cant even access that (Same error on >MODE COM5).
Any other suggestions? Thanks.

 

[Kelly]

None of this has ever been necessary within XP. How interesting in your
case. Good luck!

--
All the Best,
Kelly (MS-MVP)

Troubleshooting Windows XP
http://www.kellys-korner-xp.com

 

[Affan]

Gosh if you cant help me with this... I guess I have a problem!!!!

 

[Bob I]

Ah, this is a newsgroup with users helping users, it's not Microsoft
tech support.

 

[Kelly]

http://www.google.com/search?hl=en&lr=&c2coff=1&q=com+port+not+available+xp

http://www.google.com/search?hl=en&lr=&c2coff=1&q=com5+port+not+available+xp&btnG=Search

--
All the Best,
Kelly (MS-MVP)

Troubleshooting Windows XP
http://www.kellys-korner-xp.com

 

[Affan]

thanks kelly.. i have since then been able to get the USB to serial
converter to work. Sadly the serial port in windows doesnt work.
However, booting to linux, I can easily use it. Your above search
queries didnt help me solve the prob either

Anyway.. i have given up on using the serail port short of reinstalling
windows... but that sucks!

 

[Rodger_B]

I had the same problem with Windows XP. I could not get my modem to work on
the Serial Port (Com1).
After trying everything else that I could think of I reluctantly followed
advice to put it on Com 2 instead and it works fine.
I never have found out what is tying up Com1.

 

[Sleepless in Seattle]

The serial port(s) on the motherboard noddy - check the BIOS and see what
com ports are configured for serial port 1 and serial port 2. Typically one
would NOT use COM1 and COM2 for a modem.

P.S. This is common and very basic knowledge.

 

[Sleepless in Seattle]

Rephrase "Typically one would not use COM1 and/or COM2 for an INTERNAL modem
as the motherboard serial ports MAY be configured to use them."

If you were trying to connect an EXTERNAL modem to serial port 1 (you don't
necesarilly know it is configured as COM1) then it could be disabled. Check
the BIOS.

This is NOT an XP problem.

 

[Si Ballenger]

The serial port(s) on the motherboard noddy - check the BIOS and see what
com ports are configured for serial port 1 and serial port 2. Typically one
would NOT use COM1 and COM2 for a modem.

P.S. This is common and very basic knowledge.

On Mars maybe. What planet are you from? ;-)

 

[Affan]

I have tried that.. also if your read carefully.. i told you that it
works fine on my Fedora Core 3 partition of the same system! So I think
it is XP problem.... I have even tried to diable the serial port from
COM1 but it doesnt go away!

 

[Rodger_B]

Yes, I was talking about an external modem in my case. My internal modem is
on COM 3 and I have disabled it.

I checked the BIOS. Under "Integrated Devices (Legacy Select Options)" the
Serial Port was set to Auto. My options are Auto, COM 1, COM 3 or Off. I
have now set it to COM 1 and will try my modem on it again.

I don't know if any of this helps Affan, which is what I am trying to do. I
know that mine will work on COM 2.

 

[Rodger_B]

Affan, try this site - read "Com Port in use". Following these instructions
I have now been able to get my external modem working on COM 1.
http://www.modemsite.com/56k/xptip.asp
COM1 and COM3 share an IRQ (as do COM2 and COM4), so you can't use both at
the same time without conflicts.
I left my BIOS setting for the serial port on "Auto", so I can use my
External modem on COM1 and my Internal modem on COM 3, but NOT at the same
time - I have my Internal modem disabled and only use it as a backup for the
External modem.
That's all I've got.<s>

 

[Rodger_B]

Affan, try this site - read "Com Port in use". Following these instructions
I have now been able to get my external modem working on COM 1.
http://www.modemsite.com/56k/xptip.asp
COM1 and COM3 share an IRQ (as do COM2 and COM4), so you can't use both at
the same time without conflicts.
I left my BIOS setting for the serial port on "Auto", so I can use my
External modem on COM1 and my Internal modem on COM 3, but NOT at the same
time - I have my Internal modem disabled and only use it as a backup for the
External modem.
That's all I've got.<s>


--
Rodger_B.......... from a land down under - Sydney, Australia.

thanks kelly.. i have since then been able to get the USB to serial
converter to work. Sadly the serial port in windows doesnt work.
However, booting to linux, I can easily use it. Your above search
queries didnt help me solve the prob either

Anyway.. i have given up on using the serail port short of
reinstalling windows... but that sucks!