New answers tagged user
Even if your profile is synced with the AD, only the profile is updated... not the 'User info list" (one per site collection) that holds display information for each user. The site where the name is OK may be a site the user has browsed for the first time recently, while the other one was an "old-visited" site. You can find more info at User Information ...
Yes the user profile sync is showing to be done on schedule. As I mentioned some of the sites show the new name correctly but one or two others do not (they show the old surname). So it appears to be some kind of sync between the indexing server and some sites.
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