When some users attempt to send attachments to mail recipients, the attachments will either not be received, or not properly attach to the message in the first place.
Apple Discussions poster sladana writes:
"I have problems with attachments,actually, I cannot drag and drop the file to the message, I can only attach file (photo) if I open iphoto and then click email, otherwise, I can't even attach file via attach icon in new message, or attach file from menu bar."
For attachments that do not properly attach, sometimes the file will simply appear as greyed out, as if Mail does not recognize the filetype. This has been reported to happen with MobileMe accounts, either when using Mail or when logged into me.com. Affected users have tried rebuilding mailboxes, trashing Mail preference files, and restarting the computer, but these efforts have not fixed the problem.
It is unclear why some files will not attach to messages, but there are several possibilities for addressing this problem.
Send "Windows-friendly" attachments By default, Mail sends attachments in embedded form, which allows them to be viewed directly in the email message by the recipient. However, this can be problematic for some users so Apple has included an alternate method of attaching files which does not embed them, and instead tacks them on as a classic "attachment". To do this, open Mail and in the "Edit --> Attachments" menu select the option to "Always send windows-friendly attachments". While enabling this is usually for ensuring recipients can view attachments, it may allow Mail to load attachments again.
Send compressed versions of the file Most operating systems come with utilities to manage files compressed in the ".zip" format. In OS X users have the ability to compress files in this format right in the Finder, by right-clicking a file and selecting "Archive". This will zip the file up, which might allow Mail or the MobileMe webmail applications to properly recognize the file as a sendable attachment. The one problem with doing this is files cannot be embedded, but at least they should be sendable.
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