Mail clients will regularly connect to Exchange's autodiscover to ensure that the connection to Exchange is correctly configured. This typically happens in the background, but some mail clients (seems to be mostly Outlook 2010 and 2011) occasionally pop up something like the following:
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Allow this website to configure <Tufts email address> server settings?
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It's unclear why this happens and is still being investigated, since the autodiscover server has a proper certificate.
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