Need som help with e:/can´t find misc errors

hi!
i'm a noob at this so i tried Turkeys root guide "http://forum.xda-developers.com/showthread.php?t=814381&page=13", and everything worked just fine until i tried the Pt.3 flashing my rom and backup my phone, the guide worked just fine until this came up on my phone screen?

nandroid sd card space free 7.588mb
backing up boot...
error while dumping boot image!
e:/can´t mount cache: recovery/log
e:/can´t find misc

i'm new at this forum to, so i posted here i hope to get a quick reply?
can i continue with flashing a new room, whitout this back up or is something broken? i didn't do any thing wrong in the guide, everything worked just like the guide said.
can plz some one help me?