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:** [https://x.x.x.x:443/nuova](https://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.