After upgrading to Org 9.0.5 elpa (as part of trying out elpa for the first time ever) I get the 'pick agenda option menu'. Pickin "a" or "t" all I get is a message:
"Invalid function: org-with-silentmodifications"
OS: Corporaate tweak of Ubuntu 14.04
Emacs 24.3.1
Before doing the Org upgrade I used the version that come bundled with Emacs (Org 7.something). With the old configuration Org mode worked fine when it came to agenda view and managing todo-lists. There were some minor issues such as missing ox-latex that prompted my upgrade.
Doing an internet search for the error message I get a host of hits. So far this one is the only one that seems relevant: