Just been battling the same issue on site. Bet you're running Flash Player ver10. I was able to resolve the issue by removing flash 10 and installing Flash 9 rev159. Now it works fine!
I'm going to raise this as an issue with LANDesk since I guess this will be affecting a lot of people out there...
You can find a flash removal tool as well as download links for Flash 9 here: http://kb.adobe.com/selfservice/viewContent.do?externalId=tn_14266
Thank you! Indeed, it was Flash player 10 that didn't work.