[There's a reason that Yoda is the unofficial mascot of SBS.  Size indeed matters not.] You experience issues when you add Kerio or iCloud email accounts - THE OFFICIAL BLOG OF THE SBS DIVA
Wed, Jan 30 2013 20:11 bradley

You experience issues when you add Kerio or iCloud email accounts

So Kerio must be getting enough marketshare to get it's own KB:

You experience issues when you add Kerio or iCloud email accounts:
http://support.microsoft.com/kb/2810495/en-us?sd=rss&spid=16796

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