XML Parser does get itself into trouble every so often, especially if you've had to add/remove programs that use its services. Sometimes shared components get pooched during an app un-install.
You can try doing a repair on it through add/remove programs: MSXML Parser 6.0 offers a detect and repair option.
If you find that the parser is not installed: Microsoft KB933579, KB936181, KB954430 should lead you to the Parser and XML sutff.
You can hide almost anything until you have to put the drywall up!
