Fix My App to Send Email using TLS1.2

I have a client who has a .Net desktop app developed in 2008. The app fires off email to customers via the configured email provider settings. (I.e. username or mail app code/password, imap and smtp settings).The app seems to be coded to use TLS1.0 only. As of 4/17/2023, the email provider (Comcast in this case) will only allow TLS1.2 (or higher) encryption. I might not have access to the source code. Can you help?

Also, the same app is currently stand-alone using SQL compact version. It was connecting to a shared SQL database server at one time. Can you help with getting the app configured to point to a shared database server and database?