1. At a computer system including at least one processor and a memory, in a computer networking environment including a plurality of computing systems, a computer-implemented method for determining in an email data store which of a plurality of email mailboxes is searchable, the method comprising: an act of receiving at a web service a request to determine which of a plurality of email mailboxes is available for searching, wherein the web service allows multiple different programs to search the email data store; an act of the web service sending a query to the email data store to determine which email mailboxes are available for searching; and an act of the web service returning a list of those email mailboxes which are searchable in the data store, wherein the searchable mailboxes have an appropriate, specified version and permissions indicating that the mailbox is searchable.