I have been working on setting up an oracle instant client basic connection, using the following article:
Ran into one problem which took me a little time to figure out. The article says to add an environment variable as a “User Variable”. Since I am running a web site that has an application pool running on the NETWORK SERVICE account, and it is not possible to log on using that account and set the User Variables, they will not be available to my web app.
The solution is to add all variables as System Variables (using the lower part of the Environment variables window).
Just to be safe, I also added a variable for “ORA_HOME” with the same value as the TNS_ADMIN environment variable, namely the path to the instantclient (in my case “instantclient_11_2”) folder.