Instance Security Center (ISC) Portal not working, header showing "page not found"SummaryWhen opening the Instance Security Center Portal it loads the page, but the page is completely broken. In the header are error messages that "The page you are looking for could not be found".InstructionsThe issue is happening because the Main Menu for ISC portal is using the 'HeaderMenu' widget.In the Header Menu widget, we are calling menu template sp_ng_template.Check the sp_ng_template for this, link to navigate directly.https://Instance_name.service-now.com/nav_to.do?uri=sp_ng_template.do?sys_id=1c01e3b05b301200e39fc7ad31f91af7In order to resolve the issue, one option is to change the from custom widget to 'Header Menu' OOB widget.