Please understand that Windows Storage Server system is an OEM system. Thus the vendor of the computer should provide support for it.
Could you provide detailed description of the issue? Whether it is exactly the same as KB descripted?
In the meantime please check the file version of the file Mrxsmb20.sys. Compare it with KB2550581 to see if it is older. Then contact OEM for an update which could help update the file. If there is no specific update for the file, you could also try to install
SP2 for Windows Storage Server 2008.
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