File Upload Not Working

wpadverts-gallery.js?ver=1.3.5:272 Uncaught TypeError: Cannot read property 'size' of undefined
    at WPADVERTS.File.Uploader.Plupload.FileAdded (wpadverts-gallery.js?ver=1.3.5:272)
    at F.File.g (jquery-1.7.2.min.js?ver=1.7.2:2)
    at Function.each (jquery-1.7.2.min.js?ver=1.7.2:2)
    at WPADVERTS.File.Uploader.Plupload.FilesAdded (wpadverts-gallery.js?ver=1.3.5:261)
    at F.Uploader.g (jquery-1.7.2.min.js?ver=1.7.2:2)
    at F.Uploader.dispatchEvent (plupload.min.js?ver=2.1.9:1)
    at F.Uploader.trigger (moxie.min.js?ver=1.3.5:1)
    at plupload.min.js?ver=2.1.9:1
    at moxie.min.js?ver=1.3.5:1

The above error is being generated, resulting in the inability to upload images.

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