One of the most valuable uses of email is to send and receive attachments. Again, Mail handles file attachments similarly to other email applications you might be accustomed to.
Attaching files to messages you send can be done in the following ways:
In the message to which you want to attach files, select File, Attach File (Shift--A). Then, use the Choose File sheet to select the files you want to attach.
Click the Attach button on the New Message window's toolbar. The Choose File sheet appears; use it to select the files you want to attach to a message.
In the Choose File sheet, check the Send Windows Friendly Attachments if you are sending files to Windows users. This makes these users more likely to be able to use the files you send. You can turn on this feature so it applies to all attachments by selecting, Edit, Attachments, Always Send Windows Friendly Attachments.
Drag the files onto the New Message window.
When you place a file in a new message window, you see a thumbnail preview of the file with its icon, the filename, and its size in parentheses. If the file type is one that can be displayed in the message, such as a TIFF image or a PDF file, you actually see the contents of the file in the body of the message.
By default, Mail displays the contents of files you attach if it can. If the contents of the file are being displayed and you would rather see just an icon, open the file's contextual menu and select View as icon. The file is displayed as an icon instead. To view the file's content again, open the menu and select View in Place.
File attachments must be encoded before they can be sent. When a file is encoded, it is translated into a string of text. The application that receives the message must then decode that message so the files become usable. Encoding and decoding is handled automatically, and you can't select the encoding method used.
If recipients of your file attachments have trouble with them, see "Recipients of My Attachments Are Seeing Odd Things" in the "Troubleshooting" section at the end of this chapter.
You should also compress files you attach to email messages. Under Mac OS X version 10.3, you can compress any file in the Zip format using the Finder's Archive command. Simply select the files you want to attach to an email message, open the contextual menu, and select Archive. The files you selected are placed in a Zip file. You can then rename the file (don't change the .zip file extenstion) and attach the Zip file to the message you are sending.
Sending file attachments is simple except for one thing?the Windows versus Mac situation, which raises its ugly head in the area of file attachments, too. Basically, Mac and Windows operating systems use different file format structures. Mac files have two "forks," whereas Windows files have only one. This is a problem when you send files to Windows users because they end up with two files. One is the usable file and one is unusable to them (the names of the files is filename and _filename). Recipients can use the first one and safely ignore the second one. However, it is still confusing for them.
Mail includes a solution for this problem, which is called sending Window Friendly Attachments. This causes Mail to strip the second file away, so the Windows recipient receives only one file for each attachment. That is a good thing.
However, Mac users who receive Windows-friendly attachments might lose some features, such as thumbnail preview or information about the file. In the worst case, the file might be unusable.
You can select to attach files as Windows friendly by checking the box in the Attach File dialog box. If you always want to send files in the Windows-friendly format, select Edit, Attachments, Send Windows Friendly Attachments.
Unless you always send files to other Mac users or only to Windows users, you have to decide whether to use the Windows-friendly option each time you attach files. You should either use this option when you send files to Windows users (if you don't know which type of computer the recipient uses) or not use it if you are certain the recipient uses a Mac.
When you receive a message that has files attached to it, you see the files in the body of the message. As when you send files in a message, you see the file's icon, name, and size. If the file can be displayed in the body, such as a TIFF or PDF, the contents of the file are displayed in the message. You can use the file attachments in the following ways:
Select File, Save Attachments. Use the resulting sheet to move to a location and save the attachments.
Click the Save All button at the top of the message. Use the resulting sheet to move to a location and save the attachments.
If multiple files are attached, click the expansion triangle next to the attachment line in the message's header and work with each file individually.
Double-click a file's icon to open it; drag a file's icon from the message onto a folder on the desktop to save it there.
You can open the attachment's contextual menu and select one of the listed actions, such as Open Attachment, which opens it in its native application; Open With, which enables you to select the application in which you want the file to open; Save Attachment; or Save to Downloads folder, which saves the attachment in your designated Downloads folder.
If the contents of the file are being displayed and you would rather see just an icon, open the file's contextual menu and select View as icon. The file is displayed as an icon instead. To view the file's content again, open the menu and select View in Place.
If you have trouble viewing a message and the folder into which you want to store the file attachments, double-click the message to open it in its own window. Then you can resize the window so you can more easily see the folder into which you want to drag it.
If the files you receive are compressed, you must uncompress them before you can open them.
To learn more about uncompressing files, see "Downloading and Preparing Files," p. 411.