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Looking at the Applicability Rules that are in use by WSUS (msus) by looking in the XML files themselves there are many rules that are not documented in the MSDN Doc's or in the XSD files that come with WSUS.

For the most part I have been able to work out how Update Agent works out the rules so far with the exception of LicenseDword, which according to the XML is part of the BaseApplicabilityRules scheme but is not document at all.

It seems to be registry centric but cannot find any of the values in a registry to work out how the rule is getting evaluated.

Example XML

      <bar:LicenseDword Value="Kernel-ProductInfo" Comparison="EqualTo" Data="30" xmlns:bar="" />

All the Schema MSDN Documentation is here. The XSD files themselves are only available in the WSUS installation directory under a folder called schemas.

If anyone knows about this rule or knows what they are attempting to evaluated and how it is being done that would be very helpful.

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up vote 0 down vote accepted

You can use SLGetWindowsInformationDWORD from the Software Licensing API to get the values.

You can do it yourself by going to Registry Key:


Then looking at REG_BINARY Value ProductPolicy which is a binary storage of what apears to be key value pairs. I haven't worked out the rest of the details but at least I know an API method and a manual method for accessing this information needed to evaluate LicensedDword.

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