After the Menta file has been downloaded all other IO modules operated normally but one IO module will not come online
TAC Xenta 400 or 300 and IO modules.
The IO module that will not come online, it has a several points setup in it.
One of the points is setup incorrectly with a reference to a Universal input but in a Analog output only IO controller Xenta 491
The cause of this is most likely the IO module has been changed from its original type.
IE the original IO was a 451a but has been changed to a 491.
The Menta then was not updated correctly and a analog input was left referencing a analog output in the new controller.
Check all the points in the effected controller for correct and valid references. Once corrected download the controller.
Here is another related article