You may see that error message “To view this page ensure that Adobe Flash Player version 11.5.0 or greater is installed. ” when you open vSphere Web Client 6.0 on IE 11 on Windows 8.1. The login fields still visible, but the page go to blank after you login.

[do_widget “Language Switcher” wrap=aside title=false]

This is caused by permission control. You just need right click IE icon run as administrator.