My T60 has stopped hibernating, it has been working fine up to now. When I close the lid the "moon" light does not light up and if I open the lid a message appears "The lid closed action failed". To date I have tried setting power manage to defaul and the resetting hibernate options, ran all updates, updated bios. The operating system is XP sp2. If I press the ctl + f4 the machine does try to hibernate for a few seconds but comes back on.