There is lots of back and forth in the post but the final solution is:

. When the "EM Tools" parse the TNSNAMES.ORA file, it is finding either a white space in the very first position or something else has corrupted your files. Please recreate the TNSNAMES.ORA file either with Net8 Configuration Assistant or manually and make sure the first position of the file is not a space or blank line. You can also follow note: 164166.1 if you need more help.

Hope this helps - doesn't help me though!!!

Allie