The disk manger does not want to activate the external hard disk. Even if it is formatted by the disk manager itself!
I have an external disk (1TB) with 2 partitions (2x 500GB).
I found tips on FAQ and let run CHKDSK on Win7. There were found some fails on partition1. No change.
I found I did not update the Tuxera driver (not automatically?). So I did. No success.
I made an image of the 2 partitions an re-formatted (fast) on Win7 - no success!
I formatted by disk manager - no success!

What the hell I can do more? Step back to FAT32 again?

Götz