An end user is trying to add some colleagues to his "My Site" within SharePoint. Many of the users he is able to add without an issue. However, some others he gets the error "Firstname Surname cannot be found in the User Profile Store."
I've found others with the same issue elsewhere via Google but haven't found any solutions. Does anybody have any idea what needs to be done to resolve this problem?
Edit: I've attempted to add the same colleague to my site and received the same error so it appears to be a problem with that user who is trying to be added rather than the user who is setting up their site. Not sure how much this helps but it at least rules out one possibility.