This goes for trying to align anything.... text boxes... images. I hit any of the align buttons, to center an object or move to right or left margins.... and nothing. The objects remain stationary. This just happened tonight... was working fine up til now. Cannot figure out how to get it to work again.
Check the "align to" option.
Peter, thank you, that was it! The "Align to" option had gotten moved from "Align to Margins" to "Align to Selection". I set it back to "Align to Margins" and it's all good now! Thank you so much, that was really driving me crazy!