User profile management can be a nightmare in Sharepoint 2010 when some users reporting their job title or email address appearing incorrectly in People Picker search tool. This seems to vary if they search on Last name or First name. Depending on the situation, People Picker returns either the correct, up to date profile information or the out of date.
People Picker seems to query information not only from the Sharepoint’s User Profile table, but also from the Active Directory. So, the result with the correct, up to date profile information is the one retrieved from AD but the one with out of date information is from Sharepoint’s user info table.
So why would some of these users having out of date profile information in Sharepoint? The reason seems to be because Sharepoint automatically flag a user profile as inactive if he/she has not interacted with the site for a long period of time.
The timer job which imports/ sync the user profile information from Active Directory ignores those who are inactive, therefore when searching profiles in People Picker, we get different results.
One solution is to manually assign a user permission to a dummy list, and then remove it again. This will make the user active and hence can be later synced to update their profile.
If that still doesn’t work, you might have to write some code to update each user profile with AD data.