OK, this is driving me crazy. I'm testing out Kerberos authentication using a lab environment running Windows Server 2016 DataCenter .
I've installed instant client versions 11.2, 12.1 and 12.2 and can connect with sqlplus from this machine to databases running 11.2, 12.1 and 12.2 with no problems at all using all 9 combinations.
I'm adding sqldeveloper 18.1 into the mix, and no matter what I do I cannot get it to use the sqlnet.ora that I've configured.
I'm pointing it to the Oracle home using Database->General->Advanced, and requesting to use the OCI Driver.
Tracing SQL Developer using Process Monitor it doesn't even look for a sqlnet.ora, compare with sqlplus where I can see it looking for sqlnet.ora in various places and finding it.
I've tried various hacks that have worked for me on previously, including setting TNS_ADMIN environment but to no avail.
Is this a case of being on an unsupported operating system? I'm confused as I would expect using the OCI drivers should use the same codepath as a plain sqlplus connection.
Is this a bug? I'll probably have to bite the bullet and install Windows 10 to progress, but wonder if anyone has any ideas?