Came in this morning to a mess cause by SA crashing repeatedly over the weekend. I had two messages in my mail queue that caused SA to crash rather violently on Windows. After trying to disable various things I gave up, downloaded SA 3.0.1 and installed it on my test machine where I verified that the bug was resolved.
So, if you're running SA 3.0.0 on Windows be advised that there is a serious bug that causes it to crash. Upgrading to SA 3.0.1 appears to fix it. My recommendation: don't wait, upgrade now. Bret