Missing Partitions & Grub Lost

[Sorceror]

Running Mint KDE on a separate physical hard drive from the problem drive.
I recently emptied off a partition in order to delete it and combine it with other empty drive space to create one partition.
The KDE partition manager didn't work so I booted into a live version of Parted Magic which wouldn't do the job either.
I decided to start the installation process with another distro just to finish the partitioning and then back out before installing it.
Mint would no longer see the partition at all much less any empty space. I returned to the installation process and went ahead with installing the distro on a new partition on the same physical drive as Mint as well as recreating the original intended partition on the storage drive.
After the installation the reboot wouldn't happen as the grub seems to have been lost which I find strange as this has never happened to me when doing this before.
I managed to find a boot disc containing Super Grub 2 on it which allowed me to get back into Mint to use the PC.
KDE Partition Manager gives me a 'no valid partition table was found on this device' message when I select the storage drive leaving me with 145GB of inaccessible drive space.
As the PC is on pretty much 24/7 I can get away with the boot disc for the time being, but is there anything I can do to finally utilize the rest of the storage drive or is a reinstallation of Mint KDE required to fix all problems?

[garfie]

If I understand correctly, you have one drive running Mint and another separate drive that now has nothing on it and is not being recognised. You are unable to boot Mint from the hard drive. Some questions you would need to answer are:-
Is the drive recognised by the bios at boot?
What type of drives are they, IDE or SATA?
Is it possible you had the MBR on the drive you attempted to remove the partitions from?
If you have IDE drives, are they configured as master and slave and which boots first in the bios?
If you open up your file manager does the other drive appear, ie does it mount ok?

[garfie]

My apologies, I see you already answered the last question!

[Sorceror]

Close........it's not the separate drive that's not recognized, it's the empty space on the separate drive which I was attempting to use to create a new partition which isn't recognized. The other partitions work fine within Mint and the drive is, therefore, recognized by the bios. The only partition manager that would even work properly is the KDE one which just tells me the partition table is gone and won't allow me to do anything further with it.
They are SATA drives. I'm 99% sure that the separate drive is where I've set up the boot partition (MBR) and I know that I didn't delete it when I attempted to create the new partition, but rather think that something went wrong when attempting the installation of the second OS.
I'm tempted to use the weekend to reinstall Mint and redo all my personal settings on everything, etc. but am a little worried that the remaining usable partitions on the separate drive will be lost leading to lost data.....unless of course I go and grab yet another 1TB hard drive to back everything up onto. I was hoping to not have to part with any money on this.

[garfie]

Have you tried unplugging the drive with the operating system on it and then reformatting the other drive. That way you can be sure you're not doing anything to the drive with Mint on it