Best way to perform software testing

I just finished (mostly) a major application that I've been working on for a little over a year (off and on). It is around 86k lines of code, 50k of those is from Visual Studio's auto-generated dataset. It's largely a GUI to interacting with the database, generating reports, etc. It deals with money and manages contracts so it is important for it to be as bug free as possible.

I've walked through the code, and ran the program myself. I, for the most part, cannot find more bugs. I am however, sure there are, I've just been working on the system so long I can't see them anymore. I know there are some, because of some intermittent issues I run ac开发者_如何学Pythonross, but can never pinpoint.

How should I go about software testing in order to discover the remaining bugs?

I know this is a little late, but have you heard of Test-Driven Development?

There are lots of tests you could build to discover the "remaining" bugs:

1) Unit tests

2) Integration tests

3) Behavior/Business/Acceptance tests

You could always attend a Developer Testing Bootcamp to get more ideas.

You can involve some of your end users and do a beta test that way. The less experience they have with the application until now, the more likely they are to try things you didn't think of.

Since you didn't use TDD to write it. Your best bet now is to add as many automated tests as possible to cover common scenarios. That way, when you do find bugs, and there are ALWAYS bugs in programs, you can hopefully minimize the risk to the rest of the system when you fix them.