I ran into this one today on a fresh Ubuntu install. I was attempting to mount my NAS and configured fstab. I went to mount the share and got this error:
mount: /media/Data: cannot mount //[SHARE]/Data read-only.
The fix was to install cifs-utils via apt-get install cifs-utils
Afterwards, I was able to mount the share successfully. Of course, there may be a few other causes for this error so be sure you fit this scenario.