Section: 4.2.4 Behaviour in state GMM-DEREGISTERED
Content: The state GMM-DEREGISTERED is entered when: - the MS is switched on; - the GPRS capability has been enabled in the MS; - a GPRS detach or combined GPRS detach procedure has been performed; - a GMM procedure has failed (except routing area updating, see subclause 4.7.5); or - the MS attached for emergency bearer services is in PMM-IDLE mode and its periodic routing area update timer expires (see subclause 4.7.2.2). The selection of the appropriate substate of GMM-DEREGISTERED after switching on is described in subclause 4.2.4.1. The specific behaviour of the MS in state GMM-DEREGISTERED is described in subclause 4.2.4.2. The substate chosen when the GMM-DEREGISTERED state is returned to from another state except state GMM-NULL is described in subclause 4.2.4.3. It should be noted that transitions between the various substates of GMM-DEREGISTERED are caused by (e.g.): - insertion or removal of the SIM/USIM; - cell selection/reselection (see also 3GPP TS 43.022[ None ]  [82] and 3GPP TS 25.304[ None ]  [98]); - PLMN search; - loss/regain of coverage; or - change of RA. How various GMM procedures affect the GMM-DEREGISTERED substates and the GPRS update status is described in the detailed description of the GMM procedures in subclause 4.7.