I’m trying the free version of Piwik and I’d like to add a user already registered in Piwik, in my app.
From the users section I try to send an invitation, but it tells me it’s already registered, so where should I enter him?
Can you see this user on the users list? If not, most likely the e-mail is already in use on some other instance. We’re currently working on adding the possibility to use same e-mail address across multiple instances. For now, the workaround would be to use alias, e.g. firstname.lastname@example.org. Most mailing providers have such functionality.