GnuCash

I've been a user of GnuCash for a long time. There are many features I like about this program and as it can import common formats of other accounting software like Quicken, the migration is not that hard. However, GnuCash uses strict accounting language and certain terms you are very familiar may have the opposite meaning. If you're an accounting specialist, then it's no problem. I had to get used to that and I recommend to first read the user guide. It's clear and easy to follow.

The interface looks a bit dated but it works and only crashed once. You may need to install Strawberry Perl to get additional features like automatic exchange rate updates and similar but it's worth it.