Crunchie - He continues to send me private messages. I've just reported his last message to me. He does not allow prive messages so I have to use the forum for my reply.

He stated that PC do not sleep so called me offensive names. PC do have a sleep mode, it is called "Standby".

Tell him to keep away from putting me down. I am only making suggestions.

try logging off and back on , instead of restart ,not a fix but quicker if it works

Back to the Question - At display settings dialog > Screen Saver > Power ( might be different with Vista), your settings for the Hard drive and monitor might be set to turn off after 15 mins. I set mine to "never". These settings are usually missed and can cause problems.

Also, you probably have a USB Internet device attached. This also causes problems. Internet USB takes over the D: Driveletter if this driveletter has not been manually assigned to a drive.. You may have attached an extra drive but not assigned it a driveletter.

I have tested your recommendations. I normally “hibernate” the computer and “sleep” is disabled. I have tested with “sleep” enabled and “hibernate” disabled. The drives and DVD are all internal SATA. It used to work fine.
Bob, the SFC.EXE didn’t report anything wrong.
Thank you for time and suggestions. I’ll keep working on it.

A point of interest - were any of my suggestions helpful or do you think they were irrevelant?

It wouldnt anyway. It runs silent.

Just a question, are you using Bitlocker drive encryption or do you have an IBM/Lenovo/Sony/Apple Laptop? I ask this because my lenovo updater promoted me to dowload a hotfix precicely this error, but it seemed to only relate to that particular combination of sleep+encryption+HDAPS disk shock protection.

Secondy,check your drives policies (right click and go into properties on my computer). Disabling caching may help as ive noticed that sometimes on one of my other PCs if it shuts down too quick it doesnt seem to be able to write the cache in time, resulting in files i was using being corrupted and the disk being flagged as dirty.