You can only share your screen if you have the right kind of computer and Internet connection:
- Windows 7, 8, Vista, XP, Server 2008, 2012 (32 or 64-bit) with the latest service pack
Can't find the join.me toolbar? Maybe it's hiding. That is, if you are using more than one monitor, look for join.me on your primary monitor. It will always start on your primary monitor, even when you launch it from a secondary monitor.