>>The hyperlinks are web links and while the column still appears and is highlighted as a hyperlink they do not work.
>>
>>They aren't xlsx files they are xls.
>
>Then you can't know until you have one of these zipped and sent back to you, then compare with the original. AFAIK, the process of emailing an attachment means that the file is encoded in Base64 and should be byte-by-byte identical to the original.
>
>Actually, a simpler test before that - open the source of the sent email, select the Base64 string, convert it back to binary using strconv(), strtofile() it into a xls and then open that xls. See if that works. Perhaps it is somehow changed.

Well I know its changed or it wouldn't be half the size and I have sent one to myself via normal email (not Chilkat) and it works so something in Chilkat is changing the attachment.