Facebook Will Not Accept Photos

When trying to place a photo on Facebook, it goes through the motions but does not show the photo & the "post" button becomes greyed out. This problem has only just started. I've been posting photos on Facebook for some years. This problem is recent. Looking for a solution on Facebook it's recommended that the latest version of Adobe Flash Player should be installed. I've not previously needed Flash but I tried installing it with no success. I've now uninstalled it. Can anyone help.