Service Portal throws "Unhandled exception in GlideAjax" error in the console when a client script uses evalJSON()Issue Console throws an error "Unhandled exception in GlideAjax" in Service Portal on a catalog item with a client script that uses evalJSON();CauseThis is caused as evalJSON() is not supported in the portal and returns null.ResolutionUse JSON.parse() instead in the client script. For example change the client script from: var ga = new GlideAjax('GetUserInfo'); ga.addParam('sysparm_name', 'getUserInfo'); ga.getXML(updateUserInfo); function updateUserInfo(response){ var answer = response.responseXML.documentElement.getAttribute("answer"); if(answer){ var data = answer.evalJSON(true); g_form.setValue('employee_username', data.user_name); } } To: var ga = new GlideAjax('GetUserInfo'); ga.addParam('sysparm_name', 'getUserInfo'); ga.getXML(updateUserInfo); function updateUserInfo(response){ var answer = response.responseXML.documentElement.getAttribute("answer"); if(answer){ var data = JSON.parse(answer); g_form.setValue('employee_username', data.user_name); } }