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Wim · 08-02-2011, 09:07 AM

Hi All

I'm sorry you all seem to be having the same problem. This is something we want to get to the root cause of. We are trying to reproduce this on some HP laptops we have here, but have had no success so far. So we need your help to find the root cause.

I'm assuming that the whole PC has frozen up at this time (including the laptop screen). Also, I assume that pressing Num lock or Caps lock on the keyboard does not toggle the LED on the keyboard, which means that the PC has really locked up.

We really need the crash information from the system when this occurs. It is possible to force the PC to blue screen and write the dump information. If you are experiencing this problem, please could you follow the instructions below and create a full memory dump when the system is frozen. Once you have done this, let me know and I'll send you details of where to upload this.

Forcing a System Crash from the Keyboard
For further information see http://msdn.microsoft.com/en-us/library/ff545499.aspx

It is assumed that the system has been set-up to to produce Kernel Mode dump files. It might be worth checking. For further info see http://msdn.microsoft.com/en-us/library/ff542953.aspx. Note, you want to write a "Full memory dump" not a small memory dump.

For PS/2 keyboards ensure that the following registry key exists HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\i8042prt\Parameters\ . Create a value named CrashOnCtrlScroll , and set it equal to a REG_DWORD value of 0x01.

reg add HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\i8042prt\Parameters /v CrashOnCtrlScroll /t REG_DWORD /d 1

For USB keyboards ensure that the following registry key exists HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\kbdhid\Parameters\ . Create a value named CrashOnCtrlScroll , and set it equal to a REG_DWORD value of 0x01.

reg add HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\kbdhid\Parameters /v CrashOnCtrlScroll /t REG_DWORD /d 1

Restart the system.

Initiating a crash dump
After the above has been done, the keyboard crash can be initiated by using the following hotkey sequence:

Hold down the rightmost CTRL key, and press the SCROLL LOCK key twice, while the system is frozen.

08-02-2011, 09:07 AM	#16
Wim Senior Member Join Date: Feb 2009 Posts: 1,561	Hi All I'm sorry you all seem to be having the same problem. This is something we want to get to the root cause of. We are trying to reproduce this on some HP laptops we have here, but have had no success so far. So we need your help to find the root cause. I'm assuming that the whole PC has frozen up at this time (including the laptop screen). Also, I assume that pressing Num lock or Caps lock on the keyboard does not toggle the LED on the keyboard, which means that the PC has really locked up. We really need the crash information from the system when this occurs. It is possible to force the PC to blue screen and write the dump information. If you are experiencing this problem, please could you follow the instructions below and create a full memory dump when the system is frozen. Once you have done this, let me know and I'll send you details of where to upload this. Forcing a System Crash from the Keyboard For further information see http://msdn.microsoft.com/en-us/library/ff545499.aspx It is assumed that the system has been set-up to to produce Kernel Mode dump files. It might be worth checking. For further info see http://msdn.microsoft.com/en-us/library/ff542953.aspx. Note, you want to write a "Full memory dump" not a small memory dump. For PS/2 keyboards ensure that the following registry key exists HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\i8042prt\Parameters\ . Create a value named CrashOnCtrlScroll , and set it equal to a REG_DWORD value of 0x01. reg add HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\i8042prt\Parameters /v CrashOnCtrlScroll /t REG_DWORD /d 1 For USB keyboards ensure that the following registry key exists HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\kbdhid\Parameters\ . Create a value named CrashOnCtrlScroll , and set it equal to a REG_DWORD value of 0x01. reg add HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\kbdhid\Parameters /v CrashOnCtrlScroll /t REG_DWORD /d 1 Restart the system. Initiating a crash dump After the above has been done, the keyboard crash can be initiated by using the following hotkey sequence: Hold down the rightmost CTRL key, and press the SCROLL LOCK key twice, while the system is frozen.