Use the DISK REINIT and DISK REFIT commands. These are also
documented in Books Online.
An alternative for SQL 6.5 is ...
Stop SQL Server
Backup/copy the original .dat files on the target server, if any
Start SQL Server
Drop any databases and devices you want to recover, and delete the associated physical files
Create new devices/databases the right size, with the right names and in the right order
Stop SQL Server
Copy the original .dat files over the newly re-created ones
Start SQL Server
Thanks
J. Kusch