500.19 Error from custom MembershipProvider

I have written a custom Membership Provider and Role Provider and locally these work great. They are pulling all the correct data and writing correctly.

However, when i deploy this project to the web server; I receive a 500.19 error pointing to the web.config file. I have narrowed the issue to the declaration of the membership provider

<connectionStrings>
  <add name="ProjectConnectionString" connectionString="blahblahblah" providerName="System.Data.SqlClient" />
</connectionStrings>

<membership defaultProvider="CustomMembership">
  <providers>
    <clear/>
    <add name="CustomMembership" type="CustomMembership.CustomMembershipProvider" connectionStringName="ProjectConnectionString"
      enablePasswordRetrie开发者_JS百科val="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false"
      maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="60"
      applicationName="/" />
  </providers>
</membership>

Has anyone seen this issue before? or have an idea what could be causing it?

Technology asp.net 4.0 with mvc3 locally - VS 2010 server - Server 08

As far as i see from using google, main reason for this is insufficient permissions, as error message says. Your file permissions do not allow the IIS_IUSRS (or, if your aplication pool is running on custom user, that user) user to access web.config (or probably any of the files). One easy way to test this is to prevent remotely accessing website and add everyone full rights to that folder, just to see, that it is permission issue.