Windows 7: Does HDD instillation erase my data?

Hi!I've got a 3TB HDD. So far I had it in my desktop(Win 7 Ultimate 64bit). I made backup copies of my dvd collection on it. Now.I decided to move the HDD to a Sahrkoon mobile rack. I pluged the rack into my laptop (Win 7 Home premium 64bit). It did not show up in the explorer and it asked for initialisation. On the first screen it asked to choose from MBR and GTP as it was a brand new HDD. I chose GTP as I did befor, but still did not show up in the explorer, it wants me to create a new volume. I did not do that.
So here are my queations:
Did I erase my data by doing this?
How can I get them back and make my laptop see my hdd?



Thank you in advance!
Joe

OK, first it is important to understand that we are living through a transition in hard drive tech. Any drives larger than 2TB will require some different thinking.
The MBR file system that we have been used to for years has a limitation. For technical reasons that system cannot be used on drives or partitions larger than 2.2TB. For drives or partitions larger than 2.2TB you must use the newer GPT file system.

In addition to that it is important for everyone to know that many older hard drive enclosures cannot read drives larger than 2.2TB. So in your case it might be as simple as you need a newer hard drive enclosure.

As for your data, changing the file system format can cause you to lose your files. The good news is that all the data is still there on the disk, but the new file system hasn't "put it all together".
The first thing I would do is put the drive back in the desktop and see if you can see your files there.
If not then you could look at a free program like RECUVA to use to recover your files.

Let us know what you find.