How to install Oracle 12 C and set up oracle provider for dot net

steps 1: 

1. First step Install/Update latest Visual studio, upto VS 2017
2. Delete all old oracle clients
3. Delete oracle providers for dotnet
4. Remove regedit 
   
5. restart system.

Step2: 

download the ODT client from following link

https://www.oracle.com/database/technologies/dotnet-utilsoft-downloads.html

ODAC 12.2c Release 1 and Oracle Developer Tools for Visual Studio (12.2.0.1.1)

ODTwithODAC122011.zip411 MB (431,571,252 bytes)

Extract the zip in "c/temp" folder and hit Setup.exe, follow every thing as default, you can select the base serectory as short as possible in c-drive Mine is c:/Oracle

The installation will add oracle base path and bin path to system variables .

But check for TNS_ADMIN variable in system variables, and the value should be %oracle base%/Network\Admin\

you can change as you like 

Mine TNS_ADMIN  is c:/Orcle/TNS

Where I have my sqlnet.ora and tnsnames.ora files

STEP-3
Set up Windows Features

Step 4
Set up IIS,
Create both web and webservice ,

Common issue after oracle client installation

Network Naming: No LDAP server detected or configured.

Add the following file to TNS_ADMIN path 

ldap.ora

--not for OLDP---

Unable to Access to the path 'C:\Oracle\TNS\sqlnet.ora' is denied.

well i fixed it by creating all file under my C:\Oracle\TNS accessable to everyone 😛