如何使用web.config删除DbProviderFactories？

Question

I have problem with my ASP.NET MVC app which is using SQLSERVER 2012 Expresss for security and somehow this is conflicting with my Firebird installation which is not used in this case. Getting exception like this:

An error occurred creating the configuration section handler for system.data: Column 'InvariantName' is constrained to be unique. Value 'FirebirdSql.Data.FirebirdClient' is already present.

I have tried to enter in my web.config this:

<remove invariant="FirebirdSql.Data.FirebirdClient"/>

but that didn't work, what I have finally do I have removed this firebird entry from machine.config:

<system.data>
<DbProviderFactories>
<add name="FirebirdClient Data Provider" invariant="FirebirdSql.Data.FirebirdClient" description=".NET Framework Data Provider for Firebird" type="FirebirdSql.Data.FirebirdClient.FirebirdClientFactory, FirebirdSql.Data.FirebirdClient, Version=3.0.2.0, Culture=neutral, PublicKeyToken=3750abcc3150b00c"/><add name="FirebirdClient Data Provider" invariant="FirebirdSql.Data.FirebirdClient" description=".NET Framework Data Provider for Firebird" type="FirebirdSql.Data.FirebirdClient.FirebirdClientFactory, FirebirdSql.Data.FirebirdClient, Version=3.0.2.0, Culture=neutral, PublicKeyToken=3750abcc3150b00c"/></DbProviderFactories>

and that worked out, but th is not ideal solution bcause I still need firebird to use sometimes. Anyway to disable this entry temporarily in app web,config? Also, why I am getting such conflict to start with anyway? thanks

Answer 1

You have the same record in machine.config twice. Remove one and you'll be fine.

Answer 2

I have a similar problem and ended up with a different solution.

What happen is that I started developing my Web application in the default (root) folder IIS creates.

After that, for testing purposes I changed this option to work in a deeper folder in the same domain:

I added the name and clicked " Create Virtual Directory ". The application ran but gave me the similar problem.

What happen is that when I created the second virtual directory IIS express leave the first one there pointing to the same location. So I have the same app twice sharing Web.config hierarchically.

Solution to my problem

To solve this I just changed the port so the previous created virtual directory is not my root anymore.