Linq Getting error : Property or indexer 'AnonymousType#1.Password' cannot be assigned to -- it is read only

i have write these code for change my password  on first login but this code is getting error here is my code

using (extractDataContext context = new extractDataContext()) { var Query = (from t in context.userDetails where txtUserID.Text == t.UserID && SimpleHash.Encrypt_QueryString(txtPassword.Text ) == t.Password select new { t.Password }).Single();
if (Query!=null) { Query .Password = SimpleHash.Encrypt_QueryString(txtPassword.Text);  --> Error Shows in bolted text context.SubmitChanges(); }
}