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.

• Windows 2000 Professional operating system

• Windows 2000 Server operating system

• Windows XP operating system

• Windows Server 2003 operating system

• Windows Vista operating system

• Windows Server 2008 operating system

• Windows 7 operating system

• Windows Server 2008 R2 operating system

• Windows 8 operating system

• Windows Server 2012 operating system

• Windows 8.1 operating system

• Windows Server 2012 R2 operating system

• Windows 10 operating system

• Windows Server 2016 operating system

• Windows Server 2019 operating system

• Windows Server 2022 operating system

• Windows 11 operating system

• Windows Server 2025 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 1.7: When a DirectPlay DXDiag Usage Protocol receiver indicates support for coalescence (version level 0x00010005 or higher), a Windows sender can utilize the coalescence feature to fuse any TRANS_USERDATA message except TRANS_USERDATA_END_OF_STREAM, TRANS_USERDATA_KEEPALIVE, and TRANS_USERDATA_SEND_MESSAGE.  Windows implementations never utilize the signing feature (version level 0x00010006), even when the receiver indicates support for signing.

<2> Section 1.7: After the release of DirectX 6.0, DirectPlay versions (1) through 3A were modified to resolve to DirectPlay 4. However, DirectPlay versions (1) through 3A were last released in Windows 98 operating system Second Edition.

<3> Section 2.2.5: Only the DPNSESSION_MIGRATE_HOST (0x00000004) value is used in the Windows implementation of the ApplicationDescFlags field.

<4> Section 2.2.6: The value of the dwMsgId field changes every time a SESS_PATH_TEST message is retried.

<5> Section 2.2.7: In Windows operating systems without the DirectX 9 or later runtime installed, report versions less than 0x00010005, and do not support signing or coalescence.

<6> Section 2.2.8: In Windows operating systems without the DirectX 9 or later runtime installed, report versions less than 0x00010005, and do not support signing or coalescence.

<7> Section 2.2.11: Only the 0x00000100 value is used in the Windows implementation of the dwFlags field.

<8> Section 2.2.11: The dwDNETClientVersion field is set to one of the following values. Windows will send only 0x00000007 (DirectX 9.0) as the DirectX version number. Downgrading the DirectX version is not supported.

<9> Section 2.2.26: The dwDNETVersion field is set to one of the following values. Windows will send only 0x00000007 (DirectX 9.0) as the DirectX version number. Downgrading the DirectX version is not supported.

<10> Section 2.2.33: Only the 0x00000004 value is used in the Windows implementation of the dwFlags field.

<11> Section 2.2.33.1: Only the 0x00000002 and 0x00000100 values are used in the Windows implementation of the dwFlags field.

<12> Section 2.2.33.1: The dwDNETVersion field is set to one of the following values. Windows will send only 0x00000007 (DirectX 9.0) as the DirectX version number. Downgrading the DirectX version is not supported.

<13> Section 3.1.2.1: The Windows implementation will retry as specified despite the prescriptive indication of "MAY".

<14> Section 3.1.5.4: By default, the DXDiag application transfers the hosting to the client that has been in the chat the longest.