Mystery: How can I use Outlook to help me correct the tone and style of my email?

Did an email from last Wednesday randomly reappear at the top of your inbox? We love time travel but haven't mastered it yet, so what's going on?

It is great that we have left behind the days of "can you leave the spreadsheet so I can edit it?", collaboration has completely changed how we would as a team. However, it can come with the new issue of "who deleted cell c14?", or does it?