Serial IRQ problem - I really need help!

[Guest]

When I boot, the following message appears in event log:

While validating that \Device\Serial2 was really a serial port, the
contents of the divisor latch register was identical to the interrupt enable
and the receive registers. The device is assumed not to be a serial port and
will be deleted.

This is probably because Serial2 (COM3) is an ISA modem jumpered for IRQ5,
while the date in HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501 has IRQ4
embedded in it. I can't edit the data to correct the mismatch and I can't
uninstall COM3, since it doesn't even appear in device mgr. (probably due to
above message). However, if I try to install a serial port manually, I am
informed that COM3 is "in use." How can I get around this?

(BTW, the modem worked fine until I had to reinstall the OS, a side-effect
of working with MS to solve a problem with BITS not starting.)

 

[Dave Patrick]

This article may help you.

http://support.microsoft.com/?kbid=112584

--
Regards,

Dave Patrick ....Please no email replies - reply in newsgroup.
Microsoft Certified Professional
Microsoft MVP [Windows]
http://www.microsoft.com/protect

:
| When I boot, the following message appears in event log:
|
| While validating that \Device\Serial2 was really a serial port, the
| contents of the divisor latch register was identical to the interrupt
enable
| and the receive registers. The device is assumed not to be a serial port
and
| will be deleted.
|
| This is probably because Serial2 (COM3) is an ISA modem jumpered for IRQ5,
| while the date in HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501 has
IRQ4
| embedded in it. I can't edit the data to correct the mismatch and I can't
| uninstall COM3, since it doesn't even appear in device mgr. (probably due
to
| above message). However, if I try to install a serial port manually, I am
| informed that COM3 is "in use." How can I get around this?
|
| (BTW, the modem worked fine until I had to reinstall the OS, a
side-effect
| of working with MS to solve a problem with BITS not starting.)

 

[GHalleck]

When I boot, the following message appears in event log:

While validating that \Device\Serial2 was really a serial port, the
contents of the divisor latch register was identical to the interrupt enable
and the receive registers. The device is assumed not to be a serial port and
will be deleted.

This is probably because Serial2 (COM3) is an ISA modem jumpered for IRQ5,
while the date in HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501 has IRQ4
embedded in it. I can't edit the data to correct the mismatch and I can't
uninstall COM3, since it doesn't even appear in device mgr. (probably due to
above message). However, if I try to install a serial port manually, I am
informed that COM3 is "in use." How can I get around this?

(BTW, the modem worked fine until I had to reinstall the OS, a side-effect
of working with MS to solve a problem with BITS not starting.)

For a legacy, ISA hardware modem, the preferred solution is to
disable Serial Port 2 in bios setup. The modem should then be
set up to run off COM2/IRQ3 and there should be no more problems.

PCI modems, however, can be set up to use COM3. The PCI bus
allows sharing of resources, including IRQ's. Thus, the alternate
solution is to replace the legacy, ISA hardware modem with a PCI
hardware modem.

 

[Guest]

Can't switch to PCI modem as all PCI slots are occupied. COM2 is used to
communicate with my APC UPS and COM1 is used for a Intuos serial graphics
tablet. Question is - why did it work fine before I had to reinstall the OS?

 

[Guest]

I already tried the approach in kbid 112584, but found that there are no
entries under HKLM\SYSTEM\CurrentControlSet\Services\Serial\Parameters for me
to remove.

 

[GHalleck]

Can't switch to PCI modem as all PCI slots are occupied. COM2 is used to
communicate with my APC UPS and COM1 is used for a Intuos serial graphics
tablet. Question is - why did it work fine before I had to reinstall the OS?

In the modem applet, assign the modem a different I/O address
from that used for SerialPort 2 (probably 2F8). Set the jumper
on the modem (or program its EPROM) for I/O address of 3E8 and
COM3. Assign these values for the modem in the modem applet.
Good luck.

 

[Guest]

By modem applet, I presume you mean Phone & Modem Options in Control Panel.
Unfortunately, when I try to install my modem from diskette, the only choices
I get for connection are COM1 or COM2. COM3 has been deleted in the boot
process -- but it hasn't been deleted enough that I can reinstall it with the
correct IRQ. My modem is already jumpered for base address 3E8, COM3 and
IRQ5. What I can't understand is why the reinstall of Windows 2000 created
this problem, when everything is exactly the same (ISA slot, jumpers, etc.)
as it was when everything worked.