Bad Image Cheksum

When I try to turn on my laptop, this message shows up.

STOP: c0000221 {Bad Image Checksum}

The image comdlg32.dll is possibly corrupt.  The header checksum does not match the computer checksum.

I've heard many people say I need a disk to get the driver or whatever it is onto my computer to fix the problem.  I cannot get past this screen, and I do not have the disc any longer.  Does anyone have any possible solutions for this?  Or am I up the river without a paddle?