In Office 365 user photos Thumbnails can be viewed in Outlook Web Access, Contact Card, Thumbnail in emails, Outlook Client, Yammer, Lync Client, SharePoint (People Search / Newsfeed).
Hence it is important for an organization to set a policy and keep user photos updated. This will create a good brand image for the company as well as users to get a good Credibility, Recognition and to brand themselves in Social media such as Yammer. There are cases that users will not have professional photo updated or there is a business policy which enforces users to have professional images updated.
Either the case, Admin has to take care in enforcing this. Also there exists limitation for the user photo not to be more than 10 KB or there is no central system to manage this in Office 365.
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