An information processing apparatus stores capacity limit information of a mailbox assigned to a group, and stores information of a list of a plurality of e-mail addresses belonging to the group and set capacities of individual mailboxes corresponding to individual e-mail addresses, receives a value of a set capacity of a mailbox corresponding to an e-mail address stored in a storage unit from an administrator terminal, determines whether the set capacities of all mailboxes corresponding to the plurality of e-mail addresses that belong to the group do not exceed a capacity limit of the mailbox assigned to the group, if a set capacity is changed to the set capacity of the mailbox corresponding to the received e-mail address, and updates the value of the set capacity of the mailbox corresponding to the received e-mail address if it is determined that the set capacities do not exceed the capacity limit.