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well the window-friedlyness depends on the format of the attachment. If you send a .dmg, then your windows friend may not be able to open it.
 
The only attachments I send are image formats, like .png and .jpg. I was guessing it just adds the extensions since Windows depends on them. Thanks for the help.
 
Does anyone know how to disable the Send Windows Friendly option so it's not always ticked when you first go to attach a file?

I find it really annoying because .jpgs i send to PC's don't get sent as attachments but get embedded into the message.
 
No need. The images are not "embedded" but actually attached. The exception would be if you are sending html-formatted e-mails (boo, hiss). How they are displayed on the other end depends on how the recipient's e-mail client is configured.
 
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