| Subject | English | Russian |
| comp., MS | active mailbox | активный почтовый ящик (A mailbox that has been accessed at least once in the last 30 days) |
| comp., MS | active mailbox migration | активная миграция почтовых ящиков (The stage during the e-mail migration when the migration service is actively provisioning new cloud-based mailboxes) |
| comp., MS | Active Mailbox Subscriptions | активные подписки на почтовые ящики (A counter that measures how many active mailbox subscriptions there are at a given time) |