Right click on LW's desktop icon > properties. There should be the option to run as administrator...make sure that you choose that option.
If that doesn't help, try one of these older versions. Download the installer, then uninstall your current version. Run CCleaner, then install the version that you've just downloaded. Restart your computer & see whether LW loads properly.
LW 4.16.7:
LW basic 4.16.7.exe
LW 4.14.6:
LW basic 4.14.6.exe