I am having problems with a PLC5 20/E and a 40/E with the firmware revision of A. Every time I try and add a tag to my project it faults the processors and I have to download the program to recover from the fault. The processors return a Bus Error fault has anyone experienced this problem before? One other problem I have with a ControlLogix L55 not all of my tags show up. So when I clicked on the refresh button the processor locks up. Everything continued to run but the processor drops of the network. Currently I have other processors that are working fine. Any suggestions?