In the scenario where printers are deployed to machines via group policy either as a deployed printer or as a group policy preference and WSD ports are used an issue has been seen on Windows 7 clients when new profiles are created. In this scenario, when a new profile is created the assigned printer does not appear until a printer related task is tried or the system is rebooted. The most common case is a new user logs onto the machine creating a new profile, then opens an application such as Word, attempts to print and finds that the assigned printer is not available. Closing Word and then attempting to print again will then show the assigned printer and function normally. The issue appears related to the use of WSD ports instead of the more basic TCP/IP ports. Switching to using TCP/IP ports resolves the issue.
If you are unfamiliar with WSD ports here is a description:
The WSD Port Monitor is a new printer port monitor in Windows Vista and Windows Server 2008. This port monitor supports printing to network devices that are designed to include Web Services for Devices (WSD) technology. Web Services for Devices allows network-connected IP-based devices to advertise their functionality and offer these services to clients by using the Web Services protocol. WSD-based devices and clients communicate over the network using a series of SOAP (Simple Object Access Protocol) messages over UDP and HTTP(S). WSD for Devices provides a network plug-and-play experience that is similar to installing a USB device. Web Services for Devices also defines a security profile that may be extended to provide additional protection and authentication using device-based certificates.
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