Ok never mind i solved it. In IE9 go to tools then compatability view settings and add facebook .com to the list. :)

i am also having the same problem..it seems to have started when i updated to the new ie 9. it also has to be some settings on the computer because i can share from other computers but not this one since the update. i have allowed pop ups for fv and fb but nothing..;please help

plus it is like this for all accounts..not just 1..so again i think its the computer settings, not zynga

Have you tried the following, to make sure everything is up to date? this info is from Tony a mod here at GU
i found it on another post here it might help you........

http://zynga.custhelp.com/app/answers/detail/a_id/600

To check your Java and Adobe, try here:

http://www.java.com/en/download/installed.jsp
http://www.adobe.com/shockwave/welcome/
http://www.adobe.com/software/flash/about/

Sorry -- when I hit the share button nothing happens. I am not in full screen. I also play Cafe World and I can share in that. Hope that helps!

What happens when you hit the share button ??
are u trying to share on full screen ?
if so try it not in full screen mode sometimes my page dont show the share pop up in full screen mode
but would you let us know what happens when you try to share things it might help ppl know how to tell you to fix this problem better