I think I'm missing some required software before install. Thanks for your help, someone in my company is looking at this now.

That didn't show me any errors but I've realized that I cannot open Designer standalone, I get the error below.I've tried repairing the Designer install but it's still the same. Any ideas would be appreciated? 

I've just installed AEM Workbench v6.5.0. When I open workbench, I can login to the server and retrieve the definitions without a problem. However, when I try to open a form using Designer, I get the error below.  Any ides what could be causing this? Thanks