If you are going to be away from your computer, you can set up your email program to automatically reply to incoming emails with a message explaining that you are absent. These "Out-Of-Office" or "Vacation" replies can be a good way to let customers and friends know that you have received their message but will not be able to answer immediately. However, some caution is required when configuring your automatic replies:
Auto-replies may validate your address to spammers
Replying to spam emails can lead to an increase in the amount of spam you receive. Replies let the spammer know that your email address is valid and active and your address may be elevated to a "priority" spam list and even sold to other spammers. Lists of active and validated email addresses are valuable to spammers, because they know that list recipients are more likely to read and respond to their messages. If you configure your email program to auto-reply to all incoming email, spam messages will also receive a reply, thereby validating your email address to the spammer.
Auto-replies may let thieves know that you are away from home
To be effective, business orientated "Out-Of-Office" replies may need to specify when and how long you will be away. However, "Vacation" replies sent from your home computer should not be too specific. Otherwise, your auto-replies could inadvertently let thieves know exactly when and how long your home will be vacant. Remember that, once an email leaves your inbox, you really have very little control over who sees it and where it ends up.
Unnecessary auto-replies can waste bandwidth and clutter inboxes
When ever I send out Hoax-Slayer Newsletter notification emails, I receive dozens of "Out-Of-Office" and "Vacation" replies. In fact, every email newsletter publisher is likely to receive these unnecessary emails. Obviously, there is generally no need to send a reply to email newsletters unless you have a question or comment.
While this is not a major issue, with many thousands of email newsletters being sent out every day to millions of subscribers around the world, all those unnecessary auto-replies can quickly add up to quite significant amounts of email. Thus auto-replies can add to the gunk that already clogs the world's digital arteries.
A related problem occurs when one auto-reply triggers another auto-reply and an endless loop of inbox-clogging reply emails results.
Thus, wherever possible, you should place controls on who gets your auto reply emails and make sure that each recipient only receives one reply. For personal vacation messages you could ensure that replies are only sent to specified addresses such as those listed in your personal address book. For business "Out-Of-Office" messages, you could make sure that replies are not sent to messages diverted to your "Spam" folder. Email filters can be setup in such a way that replies are only sent to messages matching particular criteria.
There is a number of good auto-reply managers available that can work in conjunction with your email program and help you deal with the above issues. Reviews of several such programs are included on About.com and a Google search will reveal many more.
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