Is Legacy FileVault the same as "FileVault 1"?

Yes. This was the term given to "Filevault 1" (i.e., the original Filevault in Leopard) after Filevault 2 was introduced with Lion.

Just to be clear, as you asked a different question in the title to the question in the post

Legacy Filevault = "Filevault 1" (Filevault in Leopard and Snow). Filevault 2 is the name given to Filevault in Lion.

The original Filevault only encrypted users home folders. Filevault 2 starting with Lion, is quite different and encrypts the entire disk.

Lion will support in a limited sense the old Filevault (Legacy Filevault) in that if it was already enabled it will continue to be so, but you cannot encrypt new users home folders.

Normally, when you migrate an account that had FileVault turned on in Leopard/Snow Leopard, Lion will ask you if you want to turn it off. You can leave it on, but I would advise against it. Turn it off, and use FV2 instead.

FV2 is highly secure, but there is 'hole' in the whole philosophy behind it, which only applies if you have other users on your system and you give them 'startup' permissions (i.e., they have their own password for FV2).

Once a user is given startup permissions, they can in fact read your entire user home folder through Single User mode. This is a pretty obscure vulnerability and only applies under the situation I just described. If you do have other users on your system and you want your own home folder to remain out of their reach, don't give them startup permissions. Alternatively, use Disk Utility to locally encrypt sensitive folders in your own account.

I have a problem I forgot to dis able Vile fault when installing Mountain lion on top of Snow leopard and I went to Security and was surpried to see Leg acy Vile fault (sorry about the pun) it would not turn off and the screen went blank and a little grey cog spinning below ,I gave up and went to the new Vile Fault and set it it seems to be ok.

If you want to repair disk on recovery disk you have to turn of the Vile fault.

How can this be ? I can not turn off Legacy VileFault.

Message was edited by: sheffi

Yes there is always a cback door.