XP HOME Shutting down

[Jomama]

One of our users was complaining yesterday that her XP Home Comp w/SP2 was shutting down randomly.
I had just installed a new DVD drive in there a couple of weeks ago and at the time I blew it out and cleaned it up. So I dont think its heat related.
It just suddenly says Windows will now shutdown. Nothing about an error. I saw it happen a couple of times. I went to properties of My Comp>Advanced>startup and recovery>settings and unchecked Automatically Resart under the system failure. There were no more incidents that day. Here is the question. Now What?
Does this eliminate a HW problem? Should I just wait for a different error? What is my next step?

[Mesaeus]

Are there any errors in the System log ? you can find it Under Administrative Tools in the Control Panel

[doubledragon5]

When was the last time you gave the system a good cleaning? If it is real dusty inside than you could have a over heating problem.....

[Jomama]

There are a number of errors in the system log for that day and fewer for the next. Most of them are 7001 " a device attached to the system is not functioning" and the services are dhcp, dns, afd.
Also there is 8032 "browser service failed to retrieve the backup list too many times...... the backup browser is stopping"

Then another red error that appears a couple of times is ATAPI device at disk 0 has out of date firmware. That would be an ACER CD Rom. The properties show a not digitally signed driver and the provider is B.H.A Co. I went to their site but it was not much help. They are a Chinese (big surprise) co and they have support for their software but no drivers for the CD ROMS.
Checked with ACER and they dont have a driver for that model either.
I saw a place on the CD properties screen that I could disable the device. Maybe I can do that and see if the problem disappears. She has a DVD writer she can use instead.
What do you think?

Doubledragon. I dont think it is heat related as I cleaned it out real well a couple of weeks ago, as noted in my initial post.

[Mesaeus]

Instead of disabling, it might be better to physically disconnect the cdrom drive. If the problem still persists, try disconnecting the DVD instead. I've never seen a mention of out of date firmware for a cdrom drive in the System log, so that is rather supsicious and could well be the culprit. As for the dhcp/dns errors, those may be related to not having the network connected at that time. Just to be sure, could you post a system log here ? When in the log viewer, first select the System log so it's open, then right click on "System" in the left column and choose the export option (probably called "Export log" or "Export list"). You can then give a file name and it will write a .txt file. Zip this up and you will be able to include it here in a new post so we can read it.