1) Please be sure you are using Internet Explorer (not Microsoft Edge, which is the default browser for Windows 10) or Mozilla Firefox.
Google Chrome and Microsoft Edge will not run Silverlight.
2) ActiveX Filtering is active.
There blue "no not enter"
circle on the right of the address bar. Click it to disable the
filtering.
3) Isolated Storage is caused by not allowing Silverlight to save settings - Should be able to work past that, but will not be able to remember any settings (most common is Company Number)
To enable Application Storage:
Right Click, select Silverlight, go to the Application Storage tab, and mark the box to "Enable Application Storage"
4) Uninstall and reinstall Silverlight.