If you are on iOS 6, then you may have encountered a strange problem when posting a photo to Facebook. You may get an error that states “This app does not have access to your photos or videos”. Basically this means that you need to allow Facebook to access your photos.
After updating to iOS 6, when you first launch the Facebook app, you need to give authorization/access rights to the app. If you didn’t do that, then here is how you can achieve it.
Follow this method on your iPhone or iPad running on iOS 6. (There is no need to follow this method on older versions of iOS):
Open the Settings app and tap on the Privacy in the left sidebar.
Find the entry for Facebook and tap it to turn it ON.
That’s all you need to do. Now you can start uploading photos from the Camera Roll of your iPad, iPhone, or iPod Touch to Facebook. Vice versa, you can also save Facebook photos to your iOS device.