This error occurs when you try to upgrade an older version of EventSentry using a patch from a newer version.
For example, you cannot use a patch for EventSentry 2.70 to upgrade EventSentry version 2.60, since patches only contain the files that were fixed in the patch (for the version of EventSentry the patch was released for).
You will have to run the latest installer to update an older version of EventSentry to the latest version. It is not necessary to apply a patch after you have upgraded.