KB940510

I have a legit copy of Vista on my computer and I understand that KB940510
update via windows update installs this update to enable Windows Vista to
detect software that bypasses product activation and interferes with normal
Windows operation.

Will this check once? or do I have another spyware program from Microsoft
that's going to check a million times and cause system performance issues,
or as Microsoft says, interferes with normal Windows operation?

cheers