Issue suddenly began about 3 weeks ago...or I noticed it anyway. I opened devicenet to change a parameter in a drive but all nodes have a question mark on them and RSNetworks will not register them no matter what I do. I checked RSLinx and I see question marks on The DNB/E modules and on the EN2T/D modules. I made sure I had the eds files and AOI's for these modules but nothing changes. I have uninstalled Networx and changed versions several times but it comes up the same way. I am using RSLinx version 4.10 and now have RSNetworx version 28. Any ideas? Thanks in advance.