I cant able to restore data in windows server 2003

Hi All.....

I am working as a system administrator in a gaming company with 90 systems and one windows server 2003..in that server have Tape drive for take the backup purpose....

And important thing is The Domain name is "test.com".

My problem is I will take the all important data form the users and copy that data into HP DAT 72 tapes with the help tape drive...

One day...i format the server and create new Active directory with name of "Test1.com"....

Now my problem is started...I am trying to restore the data using that tapes which i take the backup in earlier time...i cont able to restore the data because it shows NOTHING.....

please help me....How to restore data....I think problem is Active directory name or else...

This information is enough for this type of problem...if u have any other information please let me know.....

Thanks in Advance.......