If you get this wonderful NX error message and are looking to fix things, I believe I have the solution:

NX> 203 NXSSH running with pid: 19955

NX> 285 Enabling check on switch command
NX> 285 Enabling skip of SSH config files
NX> 285 Setting the preferred NX options
NX> 200 Connected to address: <ip address> on port: 22
NX> 202 Authenticating user: nx
NX> 208 Using auth method: publickey
HELLO NXSERVER – Version 3.2.0-73 OS (GPL, using backend: not detected)
NX> 105 hello NXCLIENT – Version 3.2.0
NX> 134 Accepted protocol: 3.2.0
NX> 105 SET SHELL_MODE SHELL
NX> 105 SET AUTH_MODE PASSWORD
NX> 105 login
NX> 101 User: <user>
NX> 102 Password:
NX> 103 Welcome to: <host> user: <user>
NX> 105 listsession –user=”<user>” –status=”suspended,running” –geometry=”2560x1024x24+render” –type=”unix-kde”
NX> 127 Sessions list of user ‘<user>’ for reconnect:
Display Type             Session ID                       Options  Depth Screen         Status      Session Name

——- —————- ——————————– ——– —– ————– ———– ——————————

NX> 147 Server capacity: reached for user: <user>
NX> 105 startsession  –link=”adsl” –backingstore=”1″ –encryption=”1″ –cache=”128M” –images=”512M” –shmem=”1″ –shpix=”1″ –strict=”0″ –composite=”1″ –media=”0″ –session=”<session>” –type=”unix-kde” –geometry=”2560×976″ –client=”linux” –keyboard=”pc105/us” –screeninfo=”2560x976x24+render”

NX> 599 Server capacity: reached for user: <user>
NX> 500 ERROR: Last operation failed.
NX> 105 NX> 280 Exiting on signal: 15

Solution:

1. ssh onto the system
2. use top or ps to find nxagent (and maybe nx*) for your user
3. kill those processes
4. log in with nx