GPS MAKES MOUSE GO CRAZY

Here's the problem:

Part of the Windows Plug and Play module is to look for a mouse plugged into a serial port. NOTE: I haven’t seen a serial mouse in about ten years :-).

Windows does this by looking for constant activity on the serial port, a tell tail sign of a mouse plugged into the port. Guess what a GPS does?

Although I've seen several temporary fixes for this, i.e. deleting "sermouse.sys" file, etc, Ultimately, it seems like the problem reappears.

The Microsoft GPS Mouse Work-Around eliminates the problem, but is a little cumbersome to implement.

THE FIX - Disable Comm Port

The name is somewhat deceiving. Windows doesn't really disable the port, it just bypasses this port when performing the plug and play search of comm ports.

The Utility does this by writing an entry into the Windows registry. This registry entry tells the Plug and Play module to ignore a particular serial port in its search for plug and play items that may be plugged into this particular serial port.

Download and unzip the CRAZYMOUSE.ZIP file. This file contains the original "comdisable.msi" and a copy of their "comdisable.exe" file.



Install the Comdisable.msi. There are two problems, The Microsoft install file places this tool in the "Program Files" folder and there isn't a shortcut to the desktop. ALSO - there isn't a "PATH" to this folder.

This program must be run in the command window, since there isn't a PATH, you must either make a PATH or copy the comdisable.exe file to a location that has a PATH.

I chose to just copy the comdisable.exe file into the windows\system32 folder (There is a PATH to the system32 folder). You can either copy/paste the comdisable.exe from the program files folder, OR copy the exe file I included in the ZIP file.

READY TO RUN THE PROGRAM

OK, everything is installed and ready, but not yet, you need to know the GPS com port.

FIND THE GPS COM PORT

If you have a USB GPS unit, you need to know what COMM port is being assigned to the GPS. The problem is, when you plug the GPS in, the mouse starts going crazy, ARGH. To temporarily fix this, go to the Windows/System32 folder and delete the file "sermouse.sys". This temporary fix will allow you to find the comm port the GPS is plugged into. Now plug the GPS in and everything will work fine, for now. The next time you reboot, the "sermouse.sys" is reloaded from the driver cache, so it reappears again, ARGH.

You can see what comm ports are assigned by going to (WinXP) (right click my computer - PROPERTIES - HARDWARE - DEVICE MANAGER - PORTS (COMM & LPT) You should see the comm port listed.

Right click on the My Computer icon and select PROPERTIES. A window similiar to the one above will open

Click on the HARDWARE tab, then Click on the DEVICE MANAGER button.

Plug the Serial adapter into the USB port and you'll see it pop up under the Ports (COM & LPT) devices.

IMPORTANT

If your computer has multiple USB ports, OR you have a one of those adapters that multiply the number of ports. Some Serial devices will pop up as a different comm port depending on the USB port they are plugged into. i.e. the same Seriial Adapter shows up as COMM12 on one USB port, but shows up as COMM11 when plugged into the USB port next to it.

SOLUTION

While watching the DEVICE MANAGER screen, plug the Serial aADapter into each USB port. write down what comm port it gets assigned. When you perform the actual disable in the following steps, disable all the ports that USSerial adapter shows up as.

NOTE

The COMM port that you are attempting to disable must be active at the time you run the "comdisable /disable COMx" program. I open up two windows, one with the DEVICE MANAGER so I can see what com port is assigned to the Serial Adapter, and the CMD window so I can run the "comdisable /disable COMx" program.

Open a command window (START - RUN - CMD)

type "comdisable /list" to get a list of comm ports. You should see the same ports listed here.

type "comdisable /disable COMx". (x is the port you want to disable)

Do this for any comm ports that you want to exclude from Plug and Play.

REBOOT and you will have NO MORE PROBLEMS.

Waiter