I have a MicroLogix 1400 program built in RSLogix 500 (v12 file format) where every tag on the HMI responds instantly—except integer file N7. Any value I enter from the main display snaps right back to its old state, and no error banner appears. Communications are solid, and neighboring parameters in the same data table update without hesitation, so the trouble has to be inside the ladder. I’ve hunted for obvious MOV, CPT, LIM, or unconditional latch instructions that could be rewriting N7, but nothing stands out. I suspect a condition tucked away in a subroutine is getting the last word. What I need now is a fresh set of eyes to comb through the logic rung by rung, confirm exactly what is forcing N7, and show me the cleanest fix. Here’s what matters to me: • Open the file in the latest RSLogix 500 update (the project is saved in v12) so every tool is available. • Manually inspect each ladder rung—don’t rely solely on the cross-reference—until the overwriting instruction is located. • Provide a brief summary explaining where the write occurs, why it fires, and your recommended correction. • Return the corrected .RSS file (or clearly commented suggestions if you prefer I implement the change). If you’re comfortable navigating MicroLogix quirks and enjoy sleuthing elusive data writes, your help will save me hours of chasing ghosts.