6 Appendix A: Product Behavior

The information in this specification is applicable to the following Microsoft products or supplemental software. References to product versions include updates to those products.

  • Microsoft Exchange Server 2007 Service Pack 1 (SP1)

  • Microsoft Exchange Server 2010

  • Microsoft Exchange Server 2013

  • Microsoft Exchange Server 2016

  • Microsoft Exchange Server 2019

  • Windows 8.1

  • Windows 10 operating system

  • Windows Server 2016 operating system

  • Windows 11 operating system

Exceptions, if any, are noted in this section. If an update version, service pack or Knowledge Base (KB) number appears with a product name, the behavior changed in that update. The new behavior also applies to subsequent updates unless otherwise specified. If a product edition appears with the product version, behavior is different in that product edition.

Unless otherwise specified, any statement of optional behavior in this specification that is prescribed using the terms "SHOULD" or "SHOULD NOT" implies product behavior in accordance with the SHOULD or SHOULD NOT prescription. Unless otherwise specified, the term "MAY" implies that the product does not follow the prescription.

<1> Section 2.2.1.1.1.1: Exchange 2007 SP1 and the initial release version of Exchange 2010 do not set the Protocol version field to 141, 160 or 161. Microsoft Exchange Server 2010 Service Pack 1 (SP1) and Exchange 2013 do not set the Protocol version field to 160 or 161.

<2> Section 2.2.1.1.1.1: Exchange 2007 SP1 sets the Protocol version field to 121. The initial release version of Exchange 2010 sets the Protocol version field to 140.

<3> Section 2.2.1.1.2.3: Exchange 2007 SP1 accepts a Content-Type header value of either "text/xml" or "text/html" for the Autodiscover command.

<4> Section 2.2.2.1.2.13:  The X-MS-ASThrottle header and throttling are not supported in Exchange 2007 SP1 and Exchange 2010. The X-MS-ASThrottle header and throttling are supported in Exchange 2013, Exchange 2016, and Exchange 2019 but are disabled by default.

<5> Section 3.1.3:  Windows Communication Apps only support protocol versions 12.1 and 14.0.

<6> Section 3.1.5.2.3:  Windows Communication Apps ignore the Retry-After header and instead retry after a set time. The set time increases exponentially when multiple 503 errors are received.

<7> Section 3.2.5.1:  Exchange 2010 and Exchange 2013 sometimes include a Retry-After header with HTTP 503 error responses.

<8> Section 3.2.5.1:  Exchange 2013, Exchange 2016, and Exchange 2019 can be configured to track changes to the User-Agent header, but do not do so by default.

<9> Section 3.2.5.1.1:  Exchange 2013, Exchange 2016, and Exchange 2019 can be configured to use different values for the allowed number of changes and the time period.

<10> Section 3.2.5.1.1:  Exchange 2013, Exchange 2016, and Exchange 2019 can be configured to block clients for an amount of time other than 14 hours.

<11> Section 3.2.5.2:  Exchange 2007 SP1 does not return the value "16.1", "16.0", "14.1", or "14.0" in the MS-ASProtocolVersions header. The initial release version of Exchange 2010 does not return the value "16.1", "16.0" or "14.1" in the MS-ASProtocolVersions header. Exchange 2010 SP1 and Exchange 2013 do not return the value "16.1" or "16.0" in the MS-ASProtocolVersions header.