Just had Exchange 2013 CU6 update hang on Step 9 of 18: Languages. It was stuck at 0% for almost an hour. I was able to get it moving forward by disabling SCEP 2012 by killing the process and deselecting check certificate for server certificate revocation in IE. Both steps were taken nearly simultaneously and the install process for Exchange jumped up immediately. Both steps were taken based on info from:
https://social.technet.microsoft.com/Forums/exchange/en-US/2a346a37-d092-4189-8a07-e8a9971925f1/cu2-installation-hangs-on-step-9-languages?forum=exchangesvrdeploy
and
https://social.technet.microsoft.com/Forums/exchange/en-US/0975bb5e-f270-4e39-abf3-70809cd98161/exchange-2010-sp3-installation-hangs-language-pack-hell
Just wanted to post that this issue was encountered on CU6 as well. Has anyone had a similar experience or able to tell which of these two steps (or both) is actually needed?