A. Microsoft provides support for virtualizing all of Exchange 2007's roles except for UM, because UM uses a third-party Real Time Collaboration (RTC) stack. The vendor that made the stack doesn't support virtualization, so virtualizing UM would cause a support problem.
A number of companies have virtualized the UM role with no problems, but it's officially unsupported until the RTC vendor supports virtualization. UM running on early Hyper-V builds had voice quality problems but these have been resolved.Related Reading:
- How can I easily install the Windows Server 2008 roles and features that Exchange Server 2007 requires?
- When I try to perform a mailbox move, why do I get errors with accounts that have whitespace in the Name or DisplayName?
- What Mail Server Are You Using?
- Who Says You Need Microsoft Exchange Server?
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