Password length minimum: 7. Non-alphanumeric characters required: 1

Hi!
Would you please tell me why this error appears: Password length minimum: 7 Non-alphanumeric characters required: 1


I added this code:
<remove name="AspNetSqlMembershipProvider"/>
         <Add name = "AspNetSqlMembershipProvider" type = "System.Web.Security.SqlMembershipProvider, System.Web, Version = 2.0.0.0, Culture = neutral, PublicKeyToken = b03f5f7f11d50a3a" connectionStringName = "LocalSqlServer" enablePasswordRetrieval = "true" enablePasswordReset = "true "requiresQuestionAndAnswer =" false "applicationName =" / "requiresUniqueEmail =" true "passwordFormat =" Encrypted "maxInvalidPasswordAtte ...