I am getting the following errors while from the lsnrctl status
command:
C:\\Users\\pna105>lsnrctl stat
LSNRCTL for 64-bit Windows: Version 11.
In my case the listener service would not start because it was set to listen to a VPN connection as well to other serveral interfaces.
Once I connected to the VPN, it just started.
However, @Imre's trick with "lsnrctl start" put me to the right track.
I had the same problem on 11.201 on Windows. After: additional install 11.203 64bit server and client in new folders. PATH environment variable was changed right after install. Error in listener appeared after listener service restart. In my case there was a night time and number of windows updates, so windows server restart helped us. Also I cleaned listener.log file according to http://pavandba.com/tag/tns-12560-tns-protocol-adapter-error/, it was surprisingly big.