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Thursday 15 April 2010

The type name 'MembershipProvider' could not be found in the namespace 'System.Web.Security' Upgrade to ASP.NET4

I received this error after upgrading to ASP.NET 4, "The type name 'MembershipProvider' could not be found in the namespace 'System.Web.Security'. This type has been forwarded to assembly 'System.Web.ApplicationServices, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35' Consider adding a reference to that assembly. ASP.NET4."

You wont believe what I did to fix it... I added the reference that it asked for, System.Web.ApplicationServices.

This has happened since MembershipUser and Other Types in the System.Web.Security Namespace Have Been Moved

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  1. Thank you. I was having a tough time tracking this one down. Most online references indicate that it's in System.Web.Security.

  2. Thanks. MSDN still says it's in System.Web.Security.

  3. Can't get this to work in IIS for trustedProviders! Ideas?