I have two hard disks – one a 1TB and the other a 250 GB. I installed the OSes in the following order:

• Windows 7 on the first hard disk (1 TB)
• After that Kubuntu 12.04 on a partition (/dev/sdb7) on the second hard disk (250 GB)
• The second drive also contains an NTFS partition.

Now, kubuntu's bootloader was installed on the second hard drive's MBR (and successfully detected Windows 7). So, whenever I wanted to load Windows I used to select the first hard disk from the BIOS boot menu and the second hard disk whenever I wanted to load kubuntu. I know I could have set the second hard disk as the default drive, still I prefered this method.

The problem started when I installed Linux Mint 13 on the second hard disk (/dev/sdb3) and overwrote kubuntu's original MBR. Now, the GRUB just detects Mint and Windows. The MBR on the 1 TB hard disk is untouched.

Is there a way I can modify the MBR on the second hard disk now so that it will show kubuntu and Mint both?