If I drill down to the tnsnames editor and highlight a service, when I click on "PING Database" (the lighnting bolt), I get the response "Unable to find tnsping.exe".
Toad is giving you that message because it needs to find the tnsping.exe file, but the path specified in the options does not point it to the file.
You can change the path by going to View | Toad Options | Executables and clicking on the flashlight button at the end of the ‘TNS Ping’ line. This will automatically search for the tnsping.exe file and fill in the appropriate path.
