Periodically I get a message in Outlook Express asking me if I want to compact email messages. When messages are compacted a list of .bak files shows up in my Recycle Bin. What happens when emails are compacted? And are they deleted when I empty the recycle bin? I get the message asking to compact emails when my Inbox is very full. Should I agree to let the messages be compacted or should I delete messages down to a lower number in my Inbox instead? Also, sometimes when I try to open an email in a folder it will say "This message cannot be opened" or something similar. Is that perhaps because it was compacted?