Keyset does not exist WCF +SSL + Username & Password authentication

My hosting is DiscountASP.NET
 I get Error "Keyset does not exist".
Please, see error on page: http://www.healthbucket.com/HealthbucketWCF/wcfUser.svc

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Section in my web.config of wcf looks:
<serviceCredentials>
<serviceCertificate findValue="www.healthbucket.com" storeLocation="LocalMachine"
storeName="My" x509FindType="FindBySubjectName" />
<userNameAuthentication userNamePasswordValidationMode="Custom"
customUserNamePasswordValidatorType="UsernameValidator, App_code" />
</serviceCredentials>
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I think there are two errors:
1. CryptographicException: Keyset does not exist
2. The certificate 'CN=www.healthbucket.com, OU=Do ...