Files or file groups cannot be backed up because they are not online.

Problem description: an error is returned when a full backup is performed on the database. Backup statement: usemastergobackupdatabasexxxx_stodiskF: DBBACKUPxxxx_S_20080124.bak; error message: Message 3007, level 16, status 1, row 1st cannot Back Up Files or file group sysft_test because it is not online.

Problem description: an error is returned when a full backup is performed on the database. Backup statement: use master go backup database xxxx_s to disk = 'f: \ DBBACKUP \ xxxx_S_20080124.bak '. error message: Message 3007, level 16, status 1, row 1st does not allow file or file group "sysft_test" to be backed up because it is not online.

Problem description: an error is returned when a full backup is performed.
Backup statement:
Use master
Go
Backup database
Xxxx_s to disk = 'f: \ DBBACKUP \ xxxx_S_20080124.bak ';
Error message:
Message 3007, level 16, state 1, 1st rows
File or file group "sysft_test" cannot be backed up because it is not online. You can use the FILEGROUP or FILE clause to execute BACKUP to limit that only online data is included in the options.
Message 3007, level 16, state 1, 1st rows
File or file group "sysft_DocData" cannot be backed up because it is not online. You can use the FILEGROUP or FILE clause to execute BACKUP to limit that only online data is included in the options.
Message 3013, level 16, state 1, 1st rows
The backup database is being terminated abnormally.

Find the cause:
I found the cause on Microsoft's website:
This is because the full-text directory in the database is not online. To perform a full backup, SQL Server 2005 requires all database files and full-text directories in the online database.
Because one or more of the following conditions meet the full-text directory, the full-text directory may be online: • The full-text directory folder is deleted or damaged.
• You have not enabled the full-text index database.
• It is used to back up and restore the database from the Microsoft SQL Server 2000 database. Therefore, the folder does not exist in the full-text directory database to restore the database.
• Upgrade SQL Server 2000 from SQL Server 2005 to your running instance. However, full-text search cannot be accessed during the upgrade process.
• Attach a database from a location. However, you specify the correct location for the full-text directory folder.

Solution:
1. Create a full-text index
Xxxx database-> properties-> file-> use full-text index
2. Re-execute the full backup

This method is tested to solve the problem that full-text indexes cannot be created because they are not online and cannot be backed up.