Updates:
According to them, the backup is in .DAT format. DAT file was extracted from HD of the production server. It's about 9 - 10 years old and contains sensitive data. They've just found out that the DB was corrupted which caused the troubles in opening the DAT file.
I've done some research and found out that only MS SQL Server 6.5 could open that DAT file. Unfortunately, I might not be able to do the migration anymore due to schedule conflict with them. :'(
Cherrie Ann B. Domingo
Jr. Systems Analyst/Programmer
E-mail: cherrie.ann.domingo@gmail.com
Blog: http://thinkingmnemosyne.blogspot.com
Website: http://www.c2-synthesis.com, http://www.cherrieanndomingo.com