Put them back into the USB case where they are then copy them to the new internal drives.
-> You must review your backup plans. It appears you don't have backup copies.
I have just built a new desktop tower PC and retired my laptop for the time being. Due to having no space for extra drives on my laptop I have ended up with more than 8 external USB drives, that I can now fit perfectly inside my desktop; for that reason I "opened" three of my external WD USB drives, removed the USB 3.0 to SATA card and plugged them one by one inside my new desktop PC.
The problem is that even though they start up, my Windows 7 64 will not show them on my PC and if I enter disc management they are listed, but as "Unallocated" HDD's....
Worst of all, they are full of important data I cannot lose.
To make things more worrying, I tried reconnecting them to their external USB 3.0 cards and now they still show the "Unallocated" status.
I know I can format them and recover the drives, but that is not an option since they are 3TB HDD's and are full of back-up and other personal documents I dare not lose.
Any ideas why this happened? and what's more important, how to recover them...
Best regards
Spanish Flyer

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