In this paper, we propose an account provision and management (APAM) architecture for messaging services such as web mail in an emergency such as a massive earthquake. The APAM architecture stably and continually provides people (users) who hope to confirm each other's safety in a stricken area with message services, even if mobile phone lines and fixed lines are unavailable. This is realized by automatically establishing an emergent line such as a satellite line and stably providing the services from a server (emergent server) in the evacuation area. The emergent server provides all users with an emergent account and authenticates the account in the evacuation area so as to avoid traffic congestion in the emergent line (low-bandwidth line). If some users already have their own account, the emergent server and the server on the Internet binds the emergent account with their account for receiving message data from their relatives as usual. Moreover, even if users move to other evacuation areas to seek their relatives, this APAM architecture allows users to continually use the services by updating the binding information of the account. We deployed a prototype system and conducted experiments to evaluate the APAM architecture. The experimental results show that the APAM architecture can stably and continually provide 1,000 users (typical capacity of the area) with an emergent account and messaging services simultaneously.