In Self Service email templates you can add invitation links. If this link is not working, or is directing the recipient to a general log in-page, that is because the link was copied from another template into this template. To solve this issue, follow the steps:
1. Go to management
2. Go to Self Service settings
3. Go to email templates
4. Double click on the template you want to edit
5. Remove the blue link in the template text
6. Click on the button 'Merge fields' and pick the right link
7. Save the template
When creating new email templates it is thus very important to add links via the 'Merge fields'-button.