Perhaps someone can help me out. I am on a HP laptop using windows 7. I just downloaded and installed 11g database and created the tnsnames.ora and listener.ora file since the net configuration assistant seems not to work. I can't seem to get this sql developer to hook up to the dev database it returns the error above and I am at a loss after a day of trying to figure out what is going on with this. I could sure use some help here. I downloaded the most recent developer 3.0_25 64 bit and am using jr6. I had recently used jdk1.6.0_25 but with no luck so I removed it.
If you need any other information that you need to know please ask. I am not sure what you all need.
If you've not loaded your DB, then the easiest thing to do would be uninstall everything, and reboot, use some cleaning tool like ccleaner and clean the registry, then reboot again and do a clean install. When you get components that do not work, there may be way more wrong than initially appears--just start over.
Please note: the ccleaner or registry cleaning tool is for more than just cleaning up your uninstall hangarounds, it's to clean your registry so it's ready for the oracle install. Dirty registry's in Windows are suspect and cause in almost all of my failed installs on Windows based Dev boxes.