"Entry has already been added" - Two Separate App Pools

Question

I am creating a test version of an existing production site. A virtual web service application exists inside the site - and the two web configs have the same connection string.

There are no "clear" tags in the production web configs and the site and the web service co-exist merrily on two separate app pools.

On the test site however, every time I browse to the webservice URL I receive the Configuration Error "The entry 'ConnectionString' has already been added."

The test site and corresponding virtual application use their own separate app pools. Any ideas?

Thanks Jim

score 19 · Accepted Answer · answered Jun 17 '14 at 09:49

19

Web.config inheritance happens even between different appPools. If you want to stop this behavior, you should add the attribute enableConfigurationOverride="false" to your appPool in the applicationHost.config file (located in %WINDIR%\System32\inetsrv\Config and %WINDIR%\SysWOW64\inetsrv\config) as in the following example:

<add name="MyAppPool" autoStart="true" managedRuntimeVersion="v4.0" managedPipelineMode="Integrated" enableConfigurationOverride="false">
    <processModel identityType="NetworkService" />
</add>

Matteo

answered Jun 17 '14 at 09:49

Matteo Sganzetta

768
7
20

1

This is not working for me on IIS7.5 (I am assuming I should add this attribute on child App's AppPool) – HaBo Apr 14 '16 at 12:42
I don't remember and currently I don't have that environment anymore, anyway I'd try adding it to the parent appPool (or both of them) – Matteo Sganzetta Apr 14 '16 at 13:40
Worked well for me, added on the child app pool. Thanks! – RobSiklos Jun 01 '17 at 15:36

score 2 · Answer 2 · edited May 23 '17 at 12:24

2

I think the problem is related that they are one site inside the other. Like a Website with a Virtual Directory inside.

In this case... the Virtual Directory web.config is "inheriting" the parent web.config

Here you can see details of how to solve this: How to stop inheritance of <configSections>in Web.Config

Other options: https://stackoverflow.com/a/367372/7720

If the problem is in other parts of your web.config (not in the sections) you can just wrap the conflicting part with <location path="." inheritInChildApplications="false">.

Other option could be let the webservice grab the connection from the website.

edited May 23 '17 at 12:24

Community

1
1

answered Apr 29 '14 at 14:57

Romias

13,783
7
56
85

Thanks - but does this apply if the virtual application is running in a different app pool? (Configured at the folder level of IIS) – Spodgy Apr 29 '14 at 15:20
Not really sure... In my case, I THINK I HAVE different App Pools in parent and child, but as it is shared hosting not easy way to know. – Romias Apr 29 '14 at 16:09
OK.. Thanks. I've opted for changing the connection string. – Spodgy Apr 29 '14 at 16:11

"Entry has already been added" - Two Separate App Pools

2 Answers2

Linked