Catch-all Email Alias

Hosting.com does not endorse the use of catch-all aliases.  They are disabled on shared email servers, and should not be configured on cloud or dedicated servers.  The biggest reason not to use catch-alls is that they are spam magnets.  A catch-all forces the server to process every single message request to your domain, whether the address exists right now.  In many cases this can add thousands of extra messages to handle an hour, which is detrimental to server performance.  Enabling catch-all's essentially creates billions of possible receiving addresses on the server.  Many of the reasons a mail admin would have for wanting to use a catch-all can be addressed in better ways. 

Prevent Address Harvesting

One theory is that a catch-all prevents incorrectly addressed emails from letting the sender know the address does not exist.  However, it is not worth the extra load on the server.  Smartermail abuse detection settings are a better way to do this as they can block these types of connections completely.

Account for misspelled addresses

While catch-alls can be used to account for misspelled email addresses, they will receive thousands of spam messages for every valid, misspelled address.  If an email user has an easily misspelled name, create specific aliases for those misspellings, or simply let the normal delivery failure notify the sender of their error.

Temporary addresses

Catch-alls might seem to be a good idea to create temporary addresses specific to conferences, clients, or projects.  However, instead of creating every possible address under your domain, create a specific alias for the address you need.