In order to do a new/fresh install you will need to first remove any trace of the old one.
Delete all activation emails inside Outlook.
Uninstall the CRM for Outlook client using add/remove programs.
Press the Start menu and add %appdata% in the search field - this will bring you to the Roaming folder: Delete the "CRM for Outlook" folder
\Roaming\Boyum IT\CRM for Outlook\
Delete the server install using add/remove programs.
Delete the subscription file.
Manually go to one of the following folders:
C:\Program Files (x86)\Boyum IT\CRM for Outlook Server\
C:\Program Files\Boyum IT\CRM for Outlook Server\
and delete all content.