Did you know you can check to see if private messages have been read by the recipient?
If you've sent a PM to someone and you want to know if they've read it go into your private messages and click the "pm tracking" button at the bottom. The next screen you see will be split in two - the top section shows PM's unread by the recipient and the bottom section shows PM's that have been read by the recipient. Also, unless the recipient has set their online status to "hidden" you can see when they were last online.
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