Something tried to delete Microsoft messenger or corrupt it. This service cannot be deleted and would cause errors if something messed with it. There is a more detailed info if you clicked technical button on that for the direct code but it is not worth it. I would either do a system restore to before what ever you did or throw in your windows cd and see if it will repair the error. If you do not want msmsgs.exe running you can disable it in registry, do not try to delete its file location or mess with it because it will cause errors. If you have this file any were else on your system other then in the messenger folder it could be a virus.