-24958: ERR_BAOVERWRITE - file already exists, cannot overwrite 

Explanation:

This error can occur when you back up data.

You specified a backup template that was already used for a backup and was defined with the property cannot overwrite.

User Response:

Use a different backup template, change the definition of the backup template or delete the existing backup using the operating system functions.

If you delete or overwrite a backup on a data carrier, all the data saved on the data carrier is lost.

See also:

Concepts of the Database System, Backup Templates and Data Carriers