How can I within Drupal 7 make updates to an external MS SQL Server database? I have an external MS SQL Server database that I can display some of its contents within the Drupal 7 views module via the Views Database Connector module.

How can I within Drupal 7 make updates to an external MS SQL Server database?
Use the Drupal database API to manipulate the data in the other database. You can use db_set_active() to switch to the other database.