I had the same issue Running Splunk 6.2.7 on CentOS 6.7 when using Google Chrome v.46 browser on Mac OS to access Splunk Web.
However, Firefox 42.0 and Safari 9.0 on Mac OSX did not have the problem, Google Chrome v.46 on Windows did not have the same problem either. Very interesting!
Chrome on MAC OSX developer tool shows the following errors:
1. Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check http://xhr.spec.whatwg.org/.
2. Uncaught TypeError: Cannot read property 'push' of undefined
3. Uncaught TypeError: Cannot set property 'innerHTML' of undefined
4. GET http://10.2.5.1:8000/en-US/splunkd/__raw/servicesNS/admin/search/data/ui/prefs/search?output_mode=json&_=1448330686430 404 (Not Found)
... View more