win2k does not start after updating vboxguestadditions

[diplomat]

I have succefully updated to 1.5 version, then boot up to my win2k guest. After vboxguestadditions update, it gives me a blue screen during boot. I says something like this (different language version):

stop:c00026c driver couln't be loaded.
driver \SystemRoot\system32\DRIVERS\VBoxVideo.sys couln't be loaded.

error: 0xc000012f

any ideas?