Microsoft XML Parser – MSXML5.DLL
Microsoft provides several different XML parsers. The System.xml parser and the System.XML.XmlReader XML parser are included with the Microsoft .NET Framework 2.0. The MSXML parser is included in the following files: Msxml.dll, msxml2.dll, msxml3.dll, msxml4.dll, msxml5.dll, and msxml6.dll. Sub-versions of these files marked with an a or r as in msxml4r.dll are resource-only DLLs. The Windows HTTP Services (Winhttp*.dll) is also included with some versions of MSXML. The Microsoft XML parser is a Component Object Model (COM) implementation of the W3C DOM model.
More information from Microsoft on these XML parsers can be found at http://support.microsoft.com/kb/269238. More background information on XML can be found at http://en.wikipedia.org/wiki/XML.
If you're missing or getting errors on one or more of these files, you may want to download the latest version of Microsoft's .NET Framework. At the time of this writing, that was version 2.0 found at http://www.microsoft.com/downloads/details.aspx?familyid=0856eacb-4362-4b0d-8edd-aab15c5e04f5&displaylang;=en.
Unless these files are causing problems, we'd recommend leaving them in place.
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Microsoft