Right now I'm getting the above error message when I attempt to create a new user with the code from http://msdn.microsoft.com/en-us/library/ta63b872.aspx. Here is the full text from the error message:
Server Error in '/CustomMembershipProvider' Application.
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Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.
Parser Error Message: Could not load type 'Samples.AspNet.Membership.SqlMembershipProvider'.
Source Error:
Line 27: <membership defaultProvider="SqlProvider" userIsOnlineTimeWindow="15">
Line 28: <providers>
Line ...
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