# Mail Server Adapter Types

NuPoint Unified Messaging supports the IMAP and MAPI messaging protocols as adapter types for connecting to email servers for voice mail synchronization and Text-to-Speech (TTS).

## IMAP

The IMAP connector, which is deployed by default on NuPoint Unified Messaging, supports Microsoft Exchange Server 2010, 2013 and 2016, Microsoft Office 365 and Google Apps. The IMAP connector only supports one email server so it is targeted for small and medium-sized companies with one email server. Up to 1500 Advanced UM users are supported with Exchange and upto 750 Advanced UM users are supported with Office 365, and up to 2500 users are supported with Google Apps (Gmail). If your enterprise has more than 1500 users and is using Exchange, use a MAPI Gateway to connect to the server.

To set up the email server for IMAP, see the following procedures:

- Configure IMAP for Exchange/Office 365

- Configure IMAP for Google Apps

Note: In most cases, voice mail messages are sent immediately to the email server and then forwarded to the Advanced UM users. However, hosted email configurations such as Google Apps may experience slight delays due to virus scanning, anti-spam software, or routing delays caused by traffic volume. As a result, the timestamps of the original voice mail message and email audio attachment may not match.

## MAPI Gateway

Note: MAPI Gateway is not supported on Google Apps mail server and Exchange 2016 onwards.

The Messaging Application Programming Interface (MAPI) Gateway is an additional NuPoint UM component running an email gateway that interfaces the Advanced UM components using IMAP and connects to the Microsoft Exchange Server using a proprietary Microsoft MAPI protocol.

The MAPI Gateway and the Exchange Server connect using the MAPI remote procedure call (MAPI/RPC) protocol. To augment security, you can configure the Exchange Server to encrypt MAPI/RPC; it is encrypted by default on Exchange 2007 and newer.

The MAPI Gateway is a component that is installed on a separate server than the NuPoint Unified Messaging server and runs under the following Microsoft Windows Operating System (OS) types:

- Windows 7 Professional (32- and 64-bit)

- Windows 8 Professional (64-bit)

- Windows 10 (64-bit)

- Windows Server 2008 R2 (64-bit)

- Windows Server 2012 R2 (64-bit)

If your enterprise has more than 500 Advanced UM users and/or two or more Exchange Servers, then you must use a MAPI Gateway. With a MAPI Gateway, a NuPoint Unified Messaging system can support up to 2,500 Advanced UM users.

The MAPI Gateway is provided as a simple executable file that installs the MAPI Gateway components automatically.

When using MAPI Gateway, a superuser account (NPUMAdmin) is required for Advanced UM. NPUMAdmin has more privileges than the administrator account. NPUMAdmin accesses the accounts and inboxes of the users on their behalf in order to synchronize voicemail and email messages.

The MAPI Gateway and the Exchange Server must be installed in the same domain, on separate computers. In a clustered NuPoint UM environment, the MAPI Gateway receives the information it requires (user and server DNs) from the Exchange Server. Also note that in a clustered environment, each member of the cluster must be using the same version of Exchange.