Web Player 5.2.3f1 causes our games to fail

Hi, Installing the latest web player (5.2.3.f1) causes our games to fail. The loader starts (we get the Unity progress bar) then it crashes with a message : "Failed to update Unity Web Player" - "Unity Web Player update finished, but installed revision (4668002) is less than required revision (4678001). Please reinstall". Any help would be gratefully received.