SdCard is not usable with KitKat?

I am using App Backup & Restore for creating backup of my apps but with KitKat its using the internal SdCard as Storage.

When I explicitly set the external SdCard path it gives the error that it is unable to create folder,

I have also tried with creating folder under android/data/[packagename]/files/ but it is still not able to do the same.

Is there any solution so that apps can use external storage for writing files.

Note : I don't want to ROOT my Phone.