problem adding msi package to GPO

We are using Group policies for software distribution for Win2k professional desktops from last year successfully.

Recently i am facing a problem to add windows media player msi package to group policy.This msi package is created using Microsoft eneterprise Deployment kit for media player 7.1, which is a free tool available from microsoft site.I am getting the following error when try to add the msi to GP–“Add operation failed.Unable to extract deployment information from the package.Run validation on the package to ensure that the package is correct”.I have followed the default procedure and did nothing special.

Any help ?