Slow right-click context menu fix

I was facing this problem for a long time and even Microsoft support guys didn’t know why it was happening after messing with my PC using remote assistant many times. The problem persisted even after I upgraded to Windows 10. Anyway here is the fix to the slow right-click menu in my case:

Remove the following from the registry:

HKEY_CLASSES_ROOT\Directory\Background\shellex\ContextMenuHandlers\igfxcui

Taken from this link