Todoist works with my Outlook 2010 (as long as I manually ad the add-in every time), but clicking on the "add project" button produces no response.
we have released a new version of the "Todoist for Outlook" add-in.
Please remove your current Outlook add-in by accessing the Control Panel -> Add/Remove Programs and deleting "OutlookTodoist", download the new application from:
and install it.
If you still experience any issues with the new version, please let us know.