When I send attachments - for example graphic file (.mi extension from CoCreate's Designer drafting program) Thunderbird "opens" it (while sending it) as it is text file and thus makes teh message long (thousands of rows). I'm now solving this so that I make zip file. Also, there is no problems with Word's, Excel's, Adobe's files which are recognized automatically by Thunderbird. In old versions of Thunderbird I've just defined the type of each file extension (which was not recognized automatically by Thunderbird) and Thunderbird didn't open an attachment while sending the mail. In last version there is no such possibility and this is a step back. I'm sending you an example... Thank you for your answer, Dušan Lanišek TITAN d.d. Slovenia