During a patching disaster one of our 3 WFE's got dropped from the farm. When added back the Nintex Workflow and Nintex Forms icons refuse to show on the ribbon. Nintex features are activated on SC and Web. Nintex is accessible from the normal Workflows drop down and via the gear. But the Icons refuse to show unless I specifically point my browser to one of the other WFE's.
I'm stumped and pulling out the SP Solutions isn't really an option for me atm.
try to check file system on the "corrupted" WFE server.
If there are all folders in in you 14 or 15 or 16 hive folder.
I had the same issue on my newly added WFE to my farm.
Problem was, that the Nintex Forms solution was not deployed to that new WFE.