With apologies but I have hidden your post to this thread because it is not factually wholly accurate and may therefore serve only to further confuse the OP. It is not true to say that one must deactivate a former installation of MMS in order to reactivate it on a new install; there is a limit of 2 concurrent licensed activations but we have no idea whether this is the problem that @TIONGLAM-NEO has since he/she has given us no further information about even what version of MS he/she has!