Okay - so you managed to install.
Do you have a complicated partitioning scheme?
Under certain conditions the install fails without any messages leaving a fully installed system except for grub
The error message indicates this is what happened
Did you notice if the installer showed "Installing boot loader" ?
If it did not this is your error
Did you use guided partitioning? This bug (almost) only appears with guided and the solution is to reinstall and use manual partitioning
I have filed a bug report about this
Do you have removable disks and removed or added a disk?
Then the solution is here
http://www.linuxmint.com/wiki/index.php ... annot_bootThis however does not give an error message in my experience