Sometimes users have itchy hands and they accidentally deleted away the INBOX folder. If you recover the inbox folder from the mail template, all entries are gone! Sigh... "Do I really have to go through the hassle of recovering the mail file from backup???" You may ask yourself...
Here's a solution without having to go through all those troubles...
(1) First, copy the INBOX folder design element back to the mail file.
(2) Open up the ($Sent) view and copy its first column formula i.e...
@If(DeliveredDate=""; @If(PostedDate="" | @IsUnavailable(PostedDate); 58;
(3) Open up the ($All) view and paste the copied formula into the view selection and make a negation of it (this will filter off all posted documents)
i.e... SELECT !@If(DeliveredDate=""; @If(PostedDate="" | @IsUnavailable(PostedDate);
58; @If(Importance="1";124;122)); 0)
(4) Go to the "All Documents" view and drag all the documents into the new Inbox folder.
(5) Finally, set back the view selection formula for ($All) view i.e... SELECT @All