Site Backup was unable to back up %1 database %2 to %3.%12 Possible cause: %3 or its directory are not writable. Solution: ...

%11Site Backup was unable to back up %1 database %2 to %3.%12

Possible cause: %3 or its directory are not writable.
Solution: Adjust file attributes and/or permissions on %3 and its directory.

Possible cause: SQL Server problem.
Solution: 
1. Review the immediately preceding status messages from this component about SQL Server errors.
2. Verify that this computer can reach the SQL Server computer.
3. Verify that SQL Server services are running.
4. Verify that the site server can access the site database.
5. Verify that the site database, transaction log, and tempdb are not full.
6. 

If the problem persists, check the SQL Server error logs.

Possible cause: An application is using %2 or some component of its path (for example, Windows Explorer may be viewing %2's parent directory.)
Solution: Verify that %2 and its parent directories are not in use by any application.%0

Site Backup task is starting. This task will interact with the windows VSS services and the appropriate writers to create ... Site Backup was run, but the %1 token had no value. Site backup did not occur.%12 Possible cause: The current site's "Backup ... Site Backup was run, but the backup destination directory ( %1 ) is invalid. Site backup did not occur.%12 Possible cause: ... Site Backup was unable to back up %1 database %2 to %3.%12 Possible cause: %3 or its directory are not writable. Solution: ... Site Backup was unable to back up %1 database %2 to %3.%12 Possible cause: %3 or its directory are not writable. Solution: ... Site Backup was unable to back up file system object %1 to %2.%12 Possible cause: %1 is not readable, or %2 is not writable. ... Site Backup was unable to back up file system object %1 to %2.%12 Possible cause: %1 is not readable, or %2 is not writable. ... Site Backup was unable to back up registry key %1 to %2.%12 Possible cause: Site Backup was unable to connect to or set backup ... Site Backup was unable to initiate command file "%1" .%12 Possible cause: Unable to find command shell to execute this file. ...