Q: I just updated iTunes to 11.4.  No sooner done than I lost the connection to my Apple wireless keypad. Why? What can I do?

I updated iTunes to 11.4. No sooner had I done that, than I lost the connection to my wireless keyboard (Apple). Why? What can I do about it?

iMac, OSX 10.7.5

I inserted new batteries into the keyboard. That did not help. My Apple Keyboard connected by wire operates just fine.