Problem sharing contacts, calendars etc for an individual user

[mathiasholm]

As the title suggest - that is our main concern at this point. The individual users cannot log in, and add users that can see/alter their contact folder, calendar unt so weiter. The 'add user' option is greyed out under 'save'. What could cause this behaviour?

Please see the screenshots for the steps taken.

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Picture number 4 shows the 'add user' option greyed out.