Check the following registry keys (or similar)
HKLM\HARDWARE\ACPI\DSDT\LENOVO\
HKLM\HARDWARE\ACPI\FADT\LENOVO\
HKLM\HARDWARE\ACPI\RSDT\LENOVO\
They should be in the form of your model number without the hyphen and not TP-xx___
Should be the model Number without the -
Example for a Thinkpad X40 2372-GHU should be "2372GHU"
Rename the FolderName from TP-xx___ to 2372GHU
I hope this helps everyone that is having this issue!
Article ID: 43, Created On: 2/19/2009, Modified: 11/1/2013