Important Kerberos-related hotfix for IIS 7.5

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Users cannot access an IIS-hosted website after the computer password for the server is changed in Windows 7 or in Windows Server 2008 R2
https://support.microsoft.com/default.aspx?scid=kb;en-US;2545850

Essentially, if the computer acount password changes, AppPoolIdentities might be unable to perform Kerberos authentication thereafter (if IIS is restarted as well).