There is a wide range of indexing capabilities, and most people and companies don't think about this until after they've gone out and spent a lot of money on a solution. For us, "indexing" means that each email is opened as it is moved to an archive, and the message is read against a list of defined terms to create a searchable list (an index) of terms that can be accessed later.
Why is this important? It's important for the employee because we've found that employees do reuse old content and attachments, and they spend a lot of time looking for those emails. Without indexing, employee productivity would suffer as more time is wasted looking through ever-larger archive volumes. If you have a searchable master index, far less time is spent searching for content. This is even more important in legal situations. If corporate counsel is presented with a discovery order asking for specific emails from certain people with particular content, a master index allows those emails (and only those emails) to be found and turned over rapidly -- versus the time and expense of searching every message in the archive.
Consider an email archiving solution that would at least give you the choice of indexing the header information, the message body, the attachment(s), or all of the above. You don't need to use all of those options, but having them available is always recommended.
Listen to the Email archiving FAQ audiocast here.
Go back to the beginning of the Email Archiving FAQ Guide.