Can't set User Alert on one site collection for one user

Question

I'm having problems setting up an Alert for one particular user on one site collection.

I'm able to set up alerts for other users (e.g. me) on the site collection in question.

I'm also able to set up alerts for the user in question on other site collections.

When I try to add the user alert on the problem site collection & look the user up in the address book, there is no email address listed for her. However, it's there when I do the same thing on another site.

Is there a particular setting specific to each site collection which might be set differently that could be causing the problem?

Any help is greatly appreciated.

Answer 1

There is a setting in Central Administration that could affect this. In the Manage Content Databases, if the content database that houses this site collection is set to Offline, user profile information will not get replicated to it and therefore might not show the affected user if he/she is relatively new.