Brian
I know you got this resolved but if anyone else is having the problem where it won't reinstall after uninstalling (as I also did) you can delete the following registry key and the installer should continue
32bit
[HKEY_CLASSES_ROOT\CLSID\{15119A76-31E3-4C58-AD65-5BCCF704B5C5}]
64bit
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{15119A76-31E3-4C58-AD65-5BCCF704B5C5}]
For good measure I also deleted the following folder which has the license.dat file
%allusersprofile%\solarwinds
Jon