Try sending in "Plain Text" format to all receivers.

Some email clients(Outlook Express for one) do not handle Rich Text Format and
change the files to *.dat


Gord Dibben Excel MVP


On Fri, 11 Feb 2005 01:43:09 -0800, UK-Graham
wrote:

I am running Excel 2003 and yesterday I emailed (using Outlook 2003) twice to
different addresses at the same client with .xls attachments. Both times the
attachments arrived as .dat files. When I sent myself one of the messages as
a test, it arrived with the attachment OK and uncorrupted. Any ideas? is it
their virus protection maybe?