I remember hitting a Y2K bug before 2008. We were working on a huge release, updating all of our external dependencies to the last version and moving from 32 to

I remember hitting a Y2K bug before 2008. We were working on a huge release, updating all of our external dependencies to the last version and moving from 32 to 64 bit. A 3rd party commercial lib we were using at the time would parse/format %y as a 2 digit year. There was a macro definition, that when defined would handle a 4-digit year, but it was off by default. We caught it early in development, but it was still a pain in the ass rebuilding all of the projects that depended on it.