This can happen if the settings.xml file found in:
gets corrupted. Try rename it or move it somewhere else.
If 1.8.3 is the latest version that works for you, I suggest you don't bother. There is a year of changes between, many which probably requires OpenSim 0.9.2 to work satisfactory.Unfortunately, didn't help but version 1_8_3_2 works ok... uninstalled it before installing latest version.. removed left overs and flushed temp files.... have it installed as c: drive /Dayturn