SQL Server The multi-part identifier tiaans@gmail.com could not be found.

Good day all

I have a register website where in the forgot password section, i want the user to enter there email address then it will display their password.

This is my code:

SqlCommand comd = new SqlCommand("select Password from Login where [E-Mail] = tiaans@gmail.com", sqlconn);
            SqlDataAdapter da = new SqlDataAdapter(comd);

             da.Fill(dt);
             if (dt.Rows.Count > 0)
             {
                 try
                 {
                     string result = dt.Rows[0]["Password"].ToString().Trim();
                     Response.Write(result);
                 }
                 catch (SqlException p)
                 {
                     Response.Write(p.ToString());
                 }
             }

But i get an error : 

The multi-part identifier "tiaans@gmail.com" could not be bound.

I inserted the email to test.