This thread was brought to my attention – https://supportforums.cisco.com/thread/2246189
After updating Java to Update 45 – you can no longer login to UCSM (UCS Manager)
You may see one of two errors:
Login Error: java.io.IOException: Invalid Http response
Login Error: java.io.IOException: Server returned HTTP response code: 400 for URL: http://x.x.x.x:443/nuova
Cisco Bug ID: CSCuj84421
This is due to a change introduced in Java
The solution posted is to rollback to Update 25. Rolling back to Update 40 also works.