'Unknown error' when sending e-mail in Microsoft Dynamics GP

In Microsoft Dynamics GP, from the Administration navigation menu, click on Setup, click on Company and then click on E-mail Message Setup.

Verify that all of the addresses listed in the 'Have replies sent to' are valid and exist in the mail address book. If not, remove them and try the emailing of the document or report again, which should now work successfully.

Note: If emailing a document or report from the Financial or Purchasing series, verify also under that series' 'E-mail Setup' window, that the 'Have Replies Sent To' addresses are also valid and exist in the mail address book.