[ASP.NET][IIS] The .Net Framework Data Providers require Microsoft Data Access Components(MDAC). Please install Microsoft Data Access Components(MDAC) version 2.6 or later

Error :

The .Net Framework Data Providers require Microsoft Data Access Components(MDAC).  Please install Microsoft Data Access Components(MDAC) version 2.6 or later

The reason for this error is that the application pool is trying to read a registry key from the HKey_Current_User hive which isn't always loaded. The solution is as follow:

1. Open IIS management console
2. Click on "Application Pools"
3. Right-click the pool for your web site and select "Advanced Settings"
4. Change the setting "Load User Profile" to True