In his article about Microsoft’s new Exchange Server feature, Mail Tips, author Paddy discusses the advantages of Mail Tips.

I agree with Paddy that this is a beneficial feature that all users within a company will appreciate. With Mail Tips, an end user – who is a sender of an email – will get helpful information before the sender sends out the email to the recipient.

Users will get informative messages about their recipient’s status while they are creating their email messages. Microsoft Exchange Server 2010 can notify the sender of any potential problems with the email message or any statuses of the recipient that the sender should know about such as if the potential recipient is out on vacation. All of this occurs while the message is being created.

The benefit to the end user is that they can modify their email message if needed based on the information they receive about the recipient list – information that was not previously available to them in earlier releases – before they send the email out. This also has the added benefit of reducing those annoying non-delivery reports (NDRs) that administrators have to deal with from time to time.

Some of the tips that are available include the following:

• Automatic replies – This Tip informs the end user if a recipient has enabled their automatic reply message while they are on vacation or unavailable for some other reason. When an end user (sender) types in a recipient in the “To” field then the end user will receive a notification message about the recipients unavailability status.
• Recipient Count – This Tip displays the sum total of the number of recipients who will receive the email. As Paddy has already noted in his blog, “…this tip is very useful when you select Groups or distribution list”. I know from my own experience with distribution lists it would come in handy to know if the distribution list has increased or decreased recently due to personnel changes.
• External recipients – This Tip displays if any external recipients have been included in the “To” field. This can be a very useful feature if an end user had auto completion enabled and they unexpectedly ended up with a recipient on the list who should not have been there. This can happen if outside recipients have similar names to individuals internal to your organization. It has happened that confidential information has been accidentally leaked through typos or email list distributions that have not been kept up to date.
• Mailbox full – This is a nice feature that can give your end users fair warning about a recipient’s mailbox that has reached their limit of received email messages and is no longer accepting any more emails. 
• Oversized message – If there are any limits on the size of email messages within your organization then your end users can get notified that they have exceeded their limit before they are done composing it. This will allow them to make their edits so as to reduce the size of their email message before they send it out.
• Restricted recipient – Sometimes end users are not allowed to send email to a mailbox or distribution list. A Mail Tip message will be displayed notifying the sender if this condition exists.
• Invalid recipient - End users who send emails to recipients whose email addresses are no longer valid – for whatever reason such as being due to a reduction in force – will get notified of this status prior to sending out their email message.

Custom Mail Tips can also be created for individual mailboxes by the administrator. A  MailTip can be created that can be displayed when people send emails to this particular mailbox that can include up to 175 characters of text to warn users of potential issues with the mailbox. When a mailbox is added to the To, Cc or Bcc fields of a new email message then a MailTip would appear to the sender of the potential email.

The implementation of Mail Tips is very similar to the implementation of Outlook Rules and can be very useful almost immediately.

I agree that all of these Mail Tips can be very beneficial to end users because not only will the Mail Tips save the end users time but also prevent any embarrassing or confidential email messages from being sent to the wrong and possibly unintended recipients.