Liferay Vaadin Portlet - JSON Undefined Error in IE


I have a Liferay Vaadin Portlet that is working with no issues (or errors) in both Firefox and Chrome. However,
when I use Internet Explorer (Version 11) I get the following error:

Webpage error details 3 4User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET4.0C; .NET4.0E) 5Timestamp: Thu, 6 Nov 2014 17:29:44 UTC 6 7 8Message: 'JSON' is undefined 9Line: 147 10Char: 8 11Code: 0 12URI: http://XXXXXXXXXXXXX/receipt-lookup-portlet/VAADIN/vaadinBootstrap.js I know for a fact the Portlet was working in IE as well, but as some point (not sure when) it stopped working.
Any ideas?




I only get this error when pulling up the page from the server, when I pull it up from my environment I get no errors (using the same browser)

No thoughts?