I have a database creation script. I've run the script after changed the path within the 'FILENAME' option to create the database on an external hard disk and I was able to see and select data from tables as the script run with no errors. However, when I tried to connect to the database from an application and read data from database tables, an exception thrown for SQL Server error 823 "The operating system returned error 21(The device is not ready.) to SQL Server during a read at offset 0x00000000132000 in file 'Database name'. Additional messages in the SQL Server error log and system event log may provide more detail. This is a severe system-level error condition that threatens database integrity and must be corrected immediately. Complete a full database consistency check (DBCC CHECKDB). This error can be caused by many factors; for more information, see SQL Server Books Online. ". I've tried to run database consistency commands aganist it but they did not carried out and I got an error message. Also when I tried to drop or recover the database, dropping and recovering process failed. Finally, I had to make the database offline then I dropped it. I need to create such database on my external hard disk not on my primary on as I may change the operating system and I may forget back it up. Can anyone help?!!!