Thanks for your suggestions. I was finally able to resolve the problem. I went into the N1MM+ in c:/Users/userID/Documents/N1MM Logger+ and listed the files looking for a Rotor error log. I did not find an error log, but I noticed that there were several ".ini" files with rotor in the name. Some of them had also had "bak" in the same so I assumed they were older versions. I deleted all of these ".ini" files and then restarted N1MM+. After I followed the rotor setup directions from the manual using the same COMM port I had been using. After doing this the rotor started working again.
This whole problem started with the latest Window10 V1909 update. That update changed the numbering of all of my computers regular COMM ports. I spent a couple of hours sorting out the COMM port numbers for each of my connected devices and updating DXLab software settings to get my radios and rotor reconnected. When I started up N1MM+ I thought it would be as easy as changing the COMM port numbers of my radios and rotor to getting everything working again with N1MM+. Unfortunately, that wasn't the case. The radios worked fine, but the rotor would not respond. Something in the update rotor.ini file must have been causing the problem. Deleting these files and letting N1MM+ rebuild them corrected this issue.
Again thanks for your help.