if used this code: https://code.msdn.microsoft.com/windowsdesktop/CSBrowserHelperObject-59c189a2 and compiled it for 64 bit. then I installed it with 64 bit regasm ( /codebase ) it shows in IE but it doesn't work (context menu is displayed)
it works fine when compiled and regasm-ed with 32bit.
my os is windows 8, and internet explorer 11 (no enhanced protection mode)
Which version of IE are you using, 64-bit or 32-bit? I think there are two versions on 64-bit OSes. I am guessing that since you have success with the 32-bit BHO, then that means you are running 32-bit IE and of course a 64-bit BHO will not work with it.