You cannot access the PureMessage console on your Windows 2003 server after you have applied Windows 2003 service pack 2 (SP2).
This issue, which applies to PureMessage for Windows /Exchange and PureMessage Small Business Edition, occurs if you have failed to upgrade to the latest version of PureMessage, and are currently running version 2.5.1 or below.
What to do
You should upgrade your system to the current version of PureMessage.
If you are unable to upgrade your system, you must install the PureMessage console on a remote computer which is not a Windows 2003 server with SP2. This procedure is described in the startup guides, in the section 'Installing a PureMessage console on a separate computer'.
Windows 2003 SP 2 upgrades the existing Microsoft Management Console (MMC) from version 2.0 to version 3.0. MMC 3.0 is not accessible to PureMessage version 2.5.1 and lower. This issue is also seen with Windows 2003 R2.