SYMPTOMS
When you are using a Windows 2000-based computer, a serial device may be detected as a serial mouse.
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CAUSE
This problem can occur because most of the devices that are detected as serial mice that are some other type of device constantly send data to the serial port which causes the detection code to incorrectly identify the device as a serial mouse.
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RESOLUTION
To resolve this problem, obtain the latest service pack for Windows 2000 and then update the registry as instructed below. For additional information about the latest service pack for Windows 2000, click the article number below to view the article in the Microsoft Knowledge Base:
260910 (
http://support.microsoft.com/kb/260910/EN-US/) How to Obtain the Latest Windows 2000 Service Pack
The English-language version of this fix should have the following file attributes or later:
Date Time Version Size File name
------------------------------------------------------
1/17/2001 03:48p 5.0.2195.3156 13,936 Serenum.sys
WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
After you apply the hotfix or the service pack, follow these steps:
1. Start Registry Editor (Regedt32.exe). To do this, click Start, click Run, type regedt32 in the Open box, and then press ENTER.
2. For instructions on how to identify the Enumerator, DeviceID, and InstanceID for your COM Port refer to the More Information section below:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Enum\Enumerator\DeviceID\InstanceID\Device Parameters
Note that there is one InstanceID for each port.
3. On the Edit menu, click Add Value, and then add the following registry value:
Value Name: SkipEnumerations
Data Type: REG_DWORD
Radix: Hexidecimal
Value: 0 through FFFFFFFE
Note that a value of zero (0) disables the feature and device detection can resume. Each time that Plug and Play does an enumeration, it counts down one, and when it counts down to zero, it re-enumerates the hardware and then starts counting down again from the registry value. When you reboot the computer, Plug and Play starts the count again at the value that you typed.
4. Quit Registry Editor.
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WORKAROUND
To work around this problem, allow the device to be detected incorrectly, use Device Manager to disable the device that is not the port to which the device is attached, and then reboot your computer. When you do this, the port works correctly and the incorrectly detected device is disabled.
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STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows 2000 Service Pack 3. After you install Windows 2000 Service Pack 3, you must edit the registry as described in the "Resolution" section of this article.
Note that Microsoft Windows XP also includes the fixed Serenum.sys file; you must edit the registry as described in the "Resolution" section for Windows XP also.
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