-24956: ERR_BASAVETYPECON - backup type conflicts with medium definition 

Explanation:

This error can occur when you back up data or restore.

The backup type (LOG, DATA or PAGES) defined in the backup template does not match the backup type you specified when backing up or restoring.

User Response:

Change the backup type defined in the backup template or specify the backup type that matches the backup template when saving or restoring.

To restore older backups, you may have to change the definition of the backup template again.