First you have to be an administrator.
I have done this in workgroup, not Enterprise, but maybe this part is the same.
Make sure you turn off service to the vault before you do this.
If you know what the server looks like for the vault it is nothing more then folders.
You have to log into the vault server itslef and retrieve the folder representing the file you are looking for
out of an "obsolete" folder. Then move it to the desired folder and it will show up in the vault next
time you log in. Remember I am speaking how to do it in workgroup. But this might give you
a start on what to look for. If you took a training class in Enterprise, check out the manual as well.
In EPDM you can rollback to a previous version if you have permissions.
If that will not work, then you can query the database to get the ID of the file and use that ID to figure out the actual path to the file on the archive server and restore that file. I suggest that you contact your VAR for the proceedure. I would hate to tell you something that would screw up your vault.
Or if you just want one file, get it from the history, then save it over the top of the current version.