Very important BIOS settings issue
A hardware related issue has been reported on some systems with the BIOS settings of UPC and PLD. This has been seen on both standard XP system but also some systems running Windows 7 that have been reverted to XP.
When these systems hibernate or standby they do not return as expected and the system appears totally dead or still displays the “Windows: Preparing to standby…” screen.
Investigation revealed that the driver handles and passes on a IRP request (as expected in power management processing) which is never completed and the driver ‘hangs’ waiting for the completion notice. We suspect this may be a BIOS issue on these particular systems. However, we have experimented with not passing on this IRP request and in tests this did not have any ill effect and the system resumed correctly. Since 4.1.6, build 1389 the following DWORD registry entry can be used to block the driver’s IRP forward processing:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\tbupddsu\NoForwardPower=1
A .reg file to set this setting is available here.
Update – 27/09/10 – We discovered on some systems that when returning from hibernate (deep sleep) the USB device was not powered up if the IRP was not processed. In version 4.1.8, build 1880, the driver can detect that the USB device is not powered up and force a stop / start of the device to initiate power up such that the touch continues to work.
Note: We would consider this function to be a hack to overcome a hardware issue and should be used with caution.