virtualbox hanging at "net registered protocol family 2"

I was trying to start the "learning puppet virtual box" on Windows 7...and it was hanging at "net registered protocol family 2".

Enabling IO APIC fixed the issue:



this is explained also here: http://docs.puppetlabs.com/learning/index.html

in Linux , "Log in as root, with the password puppet."
In the Puppet Enterprise web console, "Log in as puppet@example.com, with the password learningpuppet"