xpra hasn't been working the last few updates.
Checked the server log, and it showed:

[EE] 2012/10/09 19:00:14 WinSwitchServer.assign_virt_utils() failed to load xpra, make sure it is installed: No module named xpra.dotxpra

Fixed that with sudo ln -s /usr/lib/xpra /usr/lib/pyshared/python2.7/ but I still can't start an xpra session.
Server:

[DD] 2012/10/09 19:12:50 WinSwitchClientChannel.start_session(afd2118e252a679a88ea6e030680402d,xpra,,read_only=False;encoding="";,None) options={'read_only': 'False', 'encoding': '""'}
[II] 2012/10/09 19:12:50 WinSwitchClientChannel.start_session(afd2118e252a679a88ea6e030680402d,xpra,,read_only=False;encoding="";) command=Command(LXTerminal: lxterminal), user=User(Administrator : f629f85ae9424587bea966f155801421)
[II] 2012/10/09 19:12:50 WinSwitchServer.start_session(User(Administrator : f629f85ae9424587bea966f155801421),xpra,Command(LXTerminal: lxterminal),,{'read_only': 'False', 'encoding': '""'},None)
[DD] 2012/10/09 19:12:50 WinSwitchServer.real_start_session(User(Administrator : f629f85ae9424587bea966f155801421),xpra,Command(LXTerminal: lxterminal),,{'read_only': 'False', 'encoding': '""'},None)

Client:

[II] 2012/10/09 19:12:03 WinSwitchApplet.do_start_session(ServerConfig(hostname.net:346729663014),Command(LXTerminal: lxterminal),xpra,None,None,False)
[II] 2012/10/09 19:12:03 WinSwitchApplet.attention(Starting LXTerminal,None)
[II] 2012/10/09 19:12:03 ServerLineConnection.do_message(f629f85ae9424587bea966f155801421,Cannot start session,You have requested an xpra session but this server does not support it,)
[II] 2012/10/09 19:12:03 WinSwitchApplet.do_notify(Cannot start session,You have requested an xpra session but this server does not support it,None,None,info,ServerConfig(hostname.net:346729663014),)
[II] 2012/10/09 19:12:03 win32_balloon.notify(5112608,Cannot start session,You have requested an xpra session but this server does not support it\nClick to Edit Server Configuration,5)
[II] 2012/10/09 19:12:03 WinSwitchApplet.attention(Cannot start session,None)
[II] 2012/10/09 19:12:03 Win32Tray.MyWndProc(5112608,1044,0,1026) NIN_BALLOONSHOW

This was with: Server: Ubuntu 12.04 64bit, Client: Windows 7 64bit Both are running v0.12.16

$ dpkg -l winswitch xpra
ii  winswitch                                  0.12.16-1
ii  xpra                                       0.6.0-5

In the first time I have made the connection to my remote computer via "New Connection" menu item. It was successful. My remote computer have been automatically added in "Servers" tab list in Configuration. But I can't connect to it via menu items. The system shows me "SSH authentication failed" message. I can only make connection via "New Connection"

P.S. Both systems - Ubuntu 10.04 P.S.S. Sorry for my English.

When I starting any remote application the program starts it twice. So I get two instances of one application. When I close one of the instances the second instance closes too.

P.S. Both systems - Ubuntu 10.04 P.S.S. Sorry for my English.