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Thank you Jose! I had MAPI/HTTP disabled on one of the mailboxes which is why I was seeing the RPC/HTTP format. Thanks again!
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When I look at the Outlook profile for mailboxes on Exchange 2016, different mailboxes have the GUID in different formats. Has anyone seen this before and know why they are different (for different mailboxes)?<br />
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Format 1: https://webmail.domain.com/mapi/emsmdb/?MailboxId=43993af8-5051-4c7a-8fc2-2f3363b083f2@domain.com<br />
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Format 2: a5fbac9f-76bc-4219-96bb-05<wbr />ca9ef839bc<wbr />@domain.co<wbr />m<br />
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<a href="https://filedb.experts-exchange.com/incoming/2017/11_w48/1213279/outlook.JPG" target="_blank" title="outlook screenshot (59 KB)"><img alt="outlook screenshot" class="file-block lazyload" style="max-width: 676px;" data-src="https://filedb.experts-exchange.com/incoming/2017/11_w48/1213279/outlook.JPG" /></a>
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outlook.JPG

When I look at the Outlook profile for mailboxes on Exchange 2016, different mailboxes have the GUID in different formats. Has anyone seen this before and know why they are different (for different mailboxes)?

Format 1: https://webmail.domain.com/mapi/emsmdb/?MailboxId=43993af8-5051-4c7a-8fc2-2f3363b083f2@domain.com

Format 2: a5fbac9f-76bc-4219-96bb-05ca9ef839bc@domain.com



Exchange 2016: Seeing different mailbox GUID formats in Outlook profile

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

Exchange

Microsoft Outlook is a personal information manager from Microsoft, available as a part of the Microsoft Office suite. Although often used mainly as an email application, it also includes a calendar, task manager, contact manager, note-taker, journal, and web browser.

Outlook

Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.