Maintenance will be performed on the IMAP mail server starting from 4.30 PM this evening continuing through the weekend. During that time, all existing mailboxes will be migrated from an old storage system to a new storage system.
It is anticipated that you will be able to continue reading and sending e-mail while this maintenance occurs. As individual mailboxes are moved, there will be a brief period in which the owner of that specific mailbox will be unable to access it (everyone else will still have access to their mailboxes). However, as soon as the mailbox has been moved, access will be automatically restored -- at worst you may need to completely close your e-mail client and re-open it (you should do this if you suddenly find your client reporting that your mailbox cannot be accessed or if it appears to contain no messages).
Incoming messages received during the maintenance will be delivered as normal. There may be brief periods where they are queued for delivery a short time later.
There is one known caveat to this process. As soon as we start this migration, we will reintroduce the sent-mail problem seen earlier this week. From the time we start maintenance until your individual mailbox is migrated you may be unable to save sent-mail to the IMAP server. You can work around this by Bcc'ing yourself a copy of the message. It might be worth doing this for any important e-mail you send over the weekend.
This is the last step of the maintenance work started last week. It is critical that we complete it for the reasons explained previously.