This occurs due to a known issue with .NET Framework 4.0 not having a Internet Explorer 11.browser file. This results in the postback script that powers the event registration form not initiating to progress to the next step.

In order to resolve the issue, either update to .NET Framework 4.5 or create a Internet Explorer 11.browser file within the existing 4.0 architecture. For more information regarding how to create the .browser file, please click here.
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