I ran into this issue when starting PL/SQL Developer:

The reason seems to be that the underlying Oracle_Client 12c MUI instance is FUBAR. As in, even the C:SoftwareOracle... folder wasn’t there anymore.

Our sys admins have looked into this and they tried to reinstall it but they failed.

So (for now?) they have installed the Oracle Client 11g version, which means I now have folder with path:

C:Softwareoracleproduct11.2.0

Containing:

client_32
client_64

Which contains the needed oci.dll file in the bin folder.

PL/SQL Developer 15.0.4 seems to be fixed to look for the 12.2.0 path, as visible in the above screenshot.

Looking into the registry seems to confirm this because under

ComputerHKEY_LOCAL_MACHINESOFTWAREOracle

I only find KEY_OraClient12Home1 which contains a lot of paths like C:SoftwareOracleproduct12.2.0client_64 (and similar variants)

It seems it is only possible to install the latest version of the PL/SQL Developer:

That’s on this url:
https://www.allroundautomations.com/products/pl-sql-developer/free-trial/

My question

How do I solve this discrepancy between Oracle and PL / SQL Developer
client versions?