Roles gone when deployed to IIS

On the development machine, I was able to login with user 'kelvin'. However, on deploying to IIS, the user 'kelvin' was not found and therefore I was unable to login. I also tried registering a new user after deploying on IIS; at the registration site, the newly created user was not added to the role 'Student' because there is no such existing roles (it exists on development machine). Can someone please help me understand why (1) the user 'kelvin' wasn't found when it is inside the DB and (2) my roles are gone?

These are my connection strings in the web.config file of my wwwroot\myapp folder.

<connectionStrings> <remove name="LocalSqlServer" /> <add name="LocalSqlServer" connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=ProjectPortal;Integrated Security=True" providerName="System.Data.SqlClient" /> ...