TOAD(11.5) - DB Connection fails with 'protocol adapter not loadable' , windows 10

It all started with me trying to import 11g db dump into 12c R2 oracle.

DB Dump - 11.02.0 Server - 12.2.0.1.0

I was getting the tns error 'could not resolve connect identifier specified'. After some research , I fixed it by adding oracle home to system variables.

Then Import command started giving 'protocol adapter not loadable error' (and same with Toad(11.5)), which I fixed by putting Oracle home path in path variable before client path variable.

After that , import using IMP command started to work but when I launch toad (which was working before adding oracle home and not after doing so) ,enter db details and hit connect, it keeps failing with a popup showing 'protocol adapter not loadable'.

Please help out.

2 Answers

The Oracle articleORA-12557: TNS:protocol adapter not loadableadvises:

There are two solutions to this issue:

1. Put the Oracle DB Home in front of the other paths in the PATH environment variable.

2. Remove ORACLE_HOME From environment Variable and re-boot PC

Solution 1 seems to say that the order of the items in the PATH variable does matter here. It is required that the Oracle DB Home be placed in front of the Oracle Client Home.

Thank you for all the responses.

I removed ORACLE_HOME and moved path to server above path to oracle client in path variable. Now, as I had to add oracle_home to fix the listener issue for which I just dropped and created new listener on 1521 using net configuration utility that comes with oracle(I also have an entry in tnsnames.ora). It is all working just fine now.