I had the same problem. It turned out it was my Adobe Type Manager 4.0. I believe if you get the current Adobe update it will fix the problem. Since I never used the Type Manager I just removed it. I was then able to Hibernate.
Here is what Microsoft told me:
In this case you've indicated that when you try to go into Standby or Hibernate, you received an error message saying that your keyboard driver is causing the problem. You have a Dell QuietKey Keyboard and are currently using "PC/AT Enhanced PS/2 Keyboard (101/102-Key)". When you first installed XP it did show your keyboard. When saying the error, you removed it to try a different driver. When you tried going back a reinstalling your old driver, it was no longer an option. You have tried different keyboard drivers and still get the same error message, just showing a different keyboard driver name. You uninstalled and unplugged your keyboard and driver and rebooted my system. Now it blames the ACPI for not being able to go into Standby or Hibernate. You called Dell and asked for a new BIOS but cannot get help from them. If I've misunderstood anything, please let me know.
In order to have a better understanding of the current status of the issue, please let me know if the keyboard error still persists. If the keyboard error still persists, please refer to the following information:
SYMPTOMS
When you are using a Standard 101/102-Key keyboard or a Microsoft Natural PS/2 keyboard, you may receive the following error message when you try to put the computer into Standby, Idle, or Hibernate mode:
The device driver for the "Standard 101/102-Key or Microsoft Natural PS/2 Keyboard" device is preventing the machine from entering standby. Please close all applications and try again. If the problem persists, you may need to update this driver.
CAUSE A
This behavior can occur if Adobe Type Manager Light or Adobe Type Manager 4.0 is installed on the computer.
RESOLUTION A
To resolve this behavior, use the Add/Remove Programs tool in Control Panel to remove Adobe Type Manager Light or Adobe Type Manager 4.0, and then restart the computer.
CAUSE B
This behavior can occur if a program installs a kernel-mode driver that attaches itself to the standard keyboard driver (I8042prt.sys) and does not support Plug and Play I/O request packets (IRPs). Examples of programs that exhibit this behavior include:
- Pgpdisk version 6.02 and 6.5 (installs Pgpmemlock.sys and Pgpdisk.sys drivers)
- Adobe Type Manager version 4.0 (installs the Atmhelpr.sys driver)
RESOLUTION B
To resolve the behavior, contact the manufacturer of your program to inquire about the availability of an updated version of the program that is designed for use with Windows XP.
To work around this behavior, uninstall the program that causes this behavior, and then restart your computer.
