Hard Drive doesn't show up after large transfer-Need Help

[Noctilux.95]

I just transferred over 200GB of back-up photos to an old Seagate USB drive. The transfer went through (took two hours) and the files showed up on the drive. But once I tried to open a single photo my MBP Retina (10.9) froze up. After restarting the computer the drive no longer shows up and I get a "The disk you inserted was not readable by this computer."
I tried the drive on my Mac Pro tower (10.8) with the same result.
I need help.

Thanks!

 

[DeltaMac]

Your screen shots show that old hard drive is formatted fat32.

That would (partly) explain the slow copy speed.
However, the volume appears to be corrupted, or is just failing.

Have you tried a First Aid/Repair Disk from Disk Utility on that drive? Might not show a lot with a Fat32 volume, then, you may have the best luck if you can try a drive repair on a Windows PC - if you have access to one.
Otherwise, there's probably not much you can do in its present state, although if you have Disk Warrior, that may help you out (or not)
If you still have those photos on a different drive, You should try erasing the drive (click on the Seagate line, then click Partition, click Partition Layout for 1 Partition, then click the Options button, and change to GUID, then OK, then click the Apply button. Name the partition, if you like. It should now be formatted Mac OS Extended (journaled), which will be OK if you don't ever need to use it on a Windows system.
I suspect that may fail, because your hard drive may be failing.
Give up, replace with a new drive, that size is still pretty cheap...

 

[asriznet]

I just transferred over 200GB of back-up photos to an old Seagate USB drive. The transfer went through (took two hours) and the files showed up on the drive. But once I tried to open a single photo my MBP Retina (10.9) froze up. After restarting the computer the drive no longer shows up and I get a "The disk you inserted was not readable by this computer."
I tried the drive on my Mac Pro tower (10.8) with the same result.
I need help.

Thanks!

It looks like the Volume is not mounting.

Any luck repairing the HDD in disk utility -> first aid?

If the HDD have additional power input connection, try that, the HDD may not have enough power coming into it.

I have a feeling, this is just software corruption, repartitioning the HDD may put it back to usable state except you will lose the data on it.

 

[Noctilux.95]

It looks like the Volume is not mounting.

Any luck repairing the HDD in disk utility -> first aid?

If the HDD have additional power input connection, try that, the HDD may not have enough power coming into it.

I have a feeling, this is just software corruption, repartitioning the HDD may put it back to usable state except you will lose the data on it.

The HDD shows up in disk utility but without the option of verifying or repairing the disk. You can see the HDD in the left column (pic 1-2) under the name, disk4s1 which wasn't given by me.

 

[DeltaMac]

The HDD shows up in disk utility but without the option of verifying or repairing the disk. You can see the HDD in the left column (pic 1-2) under the name, disk4s1 which wasn't given by me.

Very true.
That's just a generic volume name, provided by the system.
Another indication that the drive is corrupted, or just faulty.

Do you have any files stored ONLY on that drive, and important to you?
If NOT, try to remove the partition, which will remove all files, and see if that will successfully complete.
If you have files that you NEED, then you want to stop what you are doing, and try to recover your data. There's software that will help, or you can go right on up to one of the data recovery services, which can get REALLY expensive, depending on how quickly you need the files, and where you send the drive.