Good afternoon(evening).The problem is that when I went to orbit the earth and my friend also went into orbit around the earth! And I don't see him and he did not see. What's the problem?

Are you both synched?
What version are you using?

How to synchronize?
Version of ksp 0.90
Version DarkMultiPlayer 0.2.1.1

Is there a sync button right next to your name (in your friend's computer/ksp) or a sync button right next to your friend's name on your KSP? If yes, click it, then you should be able to see him.

If this button then Yes we can sync up!
We can still be the problem?

It's best to upload KSP/KSP.log to a site like pastebin and let us check over it here - There's still a possibility mods are messing up a vessel sync.

If it's not obvious we'll probably have to send builds/logs back and forth, the best way to get in touch with me is my IRC channel. There's a chat thing on both www.d-mp.org and my build server godarklight.info.tm