<p><span style="font-size: 12pt;"><strong>Symptoms</strong></span></p>
<p>When reading email in your 3rd-party mail client, you sporadically receive a pop-up stating:</p>
<p>"The UID of a message changed unexpectedly.&nbsp; This typically indicates a server bug.&nbsp; Your program may not function properly after this."</p>
<p style="padding-left: 30px;">MsgSeqNum 000: Previous UID: 12345678, New UID: 12345789.<br />Protocol: IMAP<br />Server: imap.HyperOffice.com<br />Port: 143<br />Error Code: 0x800CCCDB</p>
<p>This error occurs when you have both an IMAP connection open to a specific folder in the mail client and also a WebMail session open looking at that same folder.</p>
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<p><span style="font-size: 12pt;"><strong>Products Affected</strong></span></p>
<p>Microsoft Outlook (all versions), Mozilla Thunderbird
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<p><span style="font-size: 12pt;"><strong>Resolution</strong></span></p>
<p>Navigate away from that folder in your browser or your 3rd-party mail client.&nbsp; It is advised that you only access your mail through only one method at a time.</p>