2000 is 15 years ago - things have changed significantly in the decade and a half. Source code control systems have changed, documentation is lost, and no one remembers where the database was put so you can check the code out again, or figure out that since such an old version was used, the new software can't even read the old database because it wasn't "backed up properly".
Somewhere at work (I've worked at the same company 13 years) there are ISO files of every release I did which was source code (we did a lot of Linux back then), but those ISOs are just a tiny part of the whole release - they aren't the CVS repository we used and thus lack all the comments, and the documentation was elsewhere. And now both are separated and archived to different places, so even if they are still on the network, no one knows where they're located.
Oh, but we DID make master CD copies which are part of the BOM so production may still have a copy of them.
Then when I went on to Windows work, we used VSS for a little while, and those repos have moved and changed (thanks to VSS's habit of corrupting database, you had to stop and create a whole new repo, and each time we did, layouts change). Documentation used to be separate too... and now who knows where they are. Perhaps on some dusty tape archive sitting on a shelf.
And then we gave up and moved to BitKeeper on Linux which worked really well until now they no longer provide free licenses. Then we moved to Perforce, and now we're onto Git.
This is for long running projects too. Something like a game which after it's shipped it's abandoned? If you can access it a year later, consider yourself lucky. For us we reference other branches often enough that code stays "fresh" so you can access it slighly longer. But as business changes ... after 3-4 years the old repos get dusty and people forget how to use it and it's effectively lost.