Why can't I start a Microsoft Office application after installing Windows 2000 Service Pack 3 (SP3)?

Start the DCOM configuration utility by typing at the command prompt

dcomcnfg

Select the Default Properties tab, then select Connect from the Default Authentication Level list.

Select Identify from the Default Impersonation Level list, then click OK.br>
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Close the DCOM configuration utility.

Start Windows Explorer and navigate to the system32 folder (e.g., c:windowssystem32).

Right-click msisip.dll, select Rename from the context menu, change the filename to msisip.old, and click OK.

Reinstall Win2K SP3.

Start Windows Explorer, right-click the boot partition drive (typically the C drive, where the Windows folder resides), and select Properties from the context menu.

Select the Security tab.

Click Add.

Select the System account, click Add, then click OK.

Select the Full Control option under Allow and click OK.