Help reading Event Viewer Logs

[Cooper]

My work computer had a critical error yesterday. It said it could not find the boot disk. Reportedly, my boss pressed ctr + alt + del and it booted up. I dug into the Event Viewer logs and found the event... but I have no idea what I'm doing from there.

My boss ran Malawarebytes and found a few viruses. I'm in the middle of running it again, in case this is one of those super-nasty viruses.

Below is what I think is the important stuff, but I can post the whole log if need-be:

Event ID: 100 (I got that this is boot-up)
Version: 2
Task: 4002
Opcode: 34
Keywords: 0x8000000000010000

Anyone smarter than me know what's going on?

[Darkwolf]

Was there a usb drive in the machine? Sometimes computers will try to boot from the usb drive and then refuse to continue

[Cooper]

Was there a usb drive in the machine? Sometimes computers will try to boot from the usb drive and then refuse to continue

No, there wasn't.

[sms001]

What OS version?

Any recent changes; updates, installs, etc.?

A quick word of caution here Cooper - ANY time I get a boot disk not found error, I prepare for complete hard drive loss. Sometimes that's unnecessary, but better safe than sorry. If you have an external HD, please be sure to back up all your critical files the next time you boot; it could be the last time ever. Not likely, but well within the realm of possibility.

[Cooper]

Windows 7 64 bit, and no. My work gets mad at me if I install windows update.

And I had the same instinct. I created a 'computer emergency kit,' with hirens boot disk, ultimate boot disk, and a system restore disk.

I'm pushing them to order an external hard drive for a backup.