There are actually 17 error entries as shown below...
To eliminate this problem, I've 1) uninstalled and reinstalled all versions of either FlexsimHC or standard Flexsim2016, and 2) searched for and deleted all "prefs.t" files. Now, only FlexsimHC5 is installed on my laptop. Although the error message doesn't appear to interfere with opening and editing models, UAB reports that, plagued with the same errors, they can't start a new model.
From the text of the error message, it appears that the problem may exist in the "version upgrade prompt." Irrespective of the source, I'd like to get rid of the error and would appreciate any help doing so.