Websites or web applications which are built on web technologies such as Adobe Flash and AJAX often do not support deep linking. Currently, Mendix doesn't support deep links as well. At the moment, the confirmation link might contain the information or explanation how to finalize the registration process.
If you want to use a link to an external application, you should provide the email of a hyper link (see this question and answers).
As Fedor said there currently is no simple deeplinking solution in Mendix. You can interact between different applications using a webservice to retrieve or change data, but you cannot use the link or the webservice to open a screen in Mendix. If you really really wanted it to work you could make a screen in sharepoint that fills in all parameters and then calls a webservice to register the user in Mendix. But personally i would just let the users fill in the course in Mendix.
An easier way to support external URLS is to add an handler with an java action, using
this handler has access to the raw request data, including parameters etcetera. Those can be used to invoke a microflow, using
Core.execute(context, actionname, parammap)
so it is not to hard to achieve, although it requires a little Java knowledge. This approach has been taken for MxID as well. As context the
can be used. Be aware however, that this acts as some kind of webservice as well, since you cannot send client updates back. But for email confirmation it will do.
If you need an explanation in more detail, feel free to ask.
BTW, this is the 2.5 API, 2.4 is a bit different, but takes the same approach.
So there is no parameter passing at all? I mean from an external app to a mendix app? It would be nice if I could interact with other software. For example, a customer has its website in sharepoint and when a web site user is pressing 'register' it is forwarded to a mendix-built registration site. It is handy to have the course available as parameter.
I still would like to stress the need for this. In the mean time a will do this via a webservice. Thanks for your answers.