When should I 'Re-calculate Recipients' of a message in the Outgoing Queue?
If the ‘Left to Send’ field for an outgoing message displayes a ‘?’ symbol then the recipient information held in the Sendata.dat file has been lost. Right click the message and select ‘Recalculate Recipients’ to re-generate the recipient list in the Sendata.dat file from the information held in the message header. (NB. BCC recipient information will have been lost).