What are the drawbacks of keeping too many messages in ONE single mailbox?

A lot of email client software (e.g. Outlook Express, Outlook, Eudora etc.) stores messages in a single file if they are kept in the same mailbox in the software. It is obvious that the size of the corresponding file will grow when more and more messages are stored in the same mailbox.

Having large-size mailbox will lead to the following drawbacks:

  • It is easier for mailbox of large size to get corrupted if it is updated frequently. Since Inbox is the most frequently-updated mailbox in any email system, it will be easier to be damaged if it is very large.
  • Obviously, the larger the mailbox is, the more email data will be lost when file corruption occurs.
  • Performance of email software will become poor when reading and updating mailbox of large size.

Users are strongly recommended to perform the following actions regularly to avoid their mailboxes (esp. the Inbox) from becoming oversize:

  • Delete unwanted messages at all time.
  • DO NOT keep all email messages in your Inbox and Outbox/Sent Items. Filing your email, i.e. move/transfer as many messages as possible from Inbox and Outbox/Sent Items to other folders.
  • Split a very-large-size folder by moving its messages to several smaller-size folders. A quick way to file email messages is to store them based on their dates. For example, file all email received in June 2005 to a folder named "In200506".

Caution: create backup before compacting mailboxes

  • Compact your mailboxes regularly, especially after large amount of messages were deleted or removed.

Return to University In-house Email Service FAQ page

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