I must admit i not sure on scripting myself i didnt write the script although i was hoping someone might be able to correct the problem for me if they are able to. the path in which i wish to save the exported file is C:/Users/Tim/Desktop/Backdrops/png/
I had got the original script from this website adobe photoshop - Automating Export Layers to Files - Graphic Design Stack Exchange
which stated Replace the export path with an absolute path in your file system
this is what i have tried to do although i am slightly unsure as to which line of the script the export path is on as there are three separate lines with the names export path.