I am working from home and connected to my work's vpn. I have tried to connect to the work db with sql developer (the latest version and the previous version) on the following environments: mac os x 10.8.5 (with sql developer launched and installed directly on the iMac. sql developer launched and installed directly on a vm on same computer (guest Ubuntu 12.04 LTS) sql developer launched and installed directly on a vm on same computer (guest Windows 7.0 Professional) I get Status Failure Test Failed : IO Error - The Network Adapter could not establish the connection. I have read dba forums and googled and the most common suggestion is that the oracle listener is not up and running. I can conclusively say this is not the case because I have the option of using remote desktop and accessing the oracle db in question on my work computer. If the listener was down, according to my DBA, no one would be able to connect. My sysadmin and dba are stumped so I assume it is something unique to my home system. The reason I do not want to continue with the remote desktop workaround is because remote desktop has an annoying (infuriating often) lag.