Macs and file extensions

From D2L Wiki

When files are saved on a Mac, a file extension (e.g., ".doc" for Word documents) might not be automatically added to the file, as it is on a PC. This is fine as long as you are transferring files from Mac to Mac, but it causes problems when uploading these files to D2L. Students will not be able to download files correctly because their computer or their browser will be unable to determine the file type. So, you need to tell EACH program to add the extension, by checking the box near the lower left of the Save as box for "Append file extension."

Or, you may manually include extensions in the names of any files when saving them.

Some examples of commonly used file-type extensions follow. If you need an extension and can't figure out what it should be, contact us.

• Microsoft Word: .doc, e.g., "file.doc"
• Microsoft Excel:.xls , e.g., "file.xls"
• Microsoft PowerPoint: .ppt, e.g., "file.ppt"
• JPEG image: .jpg, e.g., "file.jpg"
• GIF image: .gif, e.g., "file.gif"
• QuickTime movie:.mov, e.g. "file.mov"

This same problem can occur if you bring the file on disk to a PC or send it in email. It is a good idea to get in the habit of always adding the appropriate extension when you save any file.