Outlook 2010 may not activate even though you have a valid activation code.  Normally you should would select the 'phone activate' option in the wizard, but if even this is not available then try the following steps:

1. Confirm that there is a folder called "C:\Program Files(x86)\Microsoft Office\Office14"
2. There should be a vbscript called ospp
3. Open a command prompt as an  'Administrator'
4. Navigate to this folder
5. Enter the command cscript ospp.vbs /puserops

This should either complete the activation or offer the phone activation option

See also http://www.kernelbytes.co.uk/?p=816