Hi William,
From the given screen shot it seems like your machine does not have visual studio 2005 not installed in your machine or it may not be properly installed.
Please have a look at the “Software Requirements” topic in the readme file.
http://www2.syncfusion.com/Installs/v5.1.0.51/release_notes/readme.htmPlease install the VS2005 to work with version 5.1. If you have already installed VS2005, please reinstall the VS2005 and let me know if you are facing the same issue.
Thank you for your interest in Essential Studio.
Regards,
Ramu