If you’re with PDFF, then check the back install locally on your machines. I’ve tried it on multiple machines without success, and that includes a complete registry wipe (manually, which is always unclean).
I suspect either the uninstaller does not clean up enough (there were a ton of reg keys still present), and/or the installer for older versions kicks off some sort of auto-update. Probably the uninstall cleanup is the problem. This may not be a care-about from your point-of-view (you want to prevent back-installs, and what better way than with an uninstall bug), but consider this: your 2.1 release is corrupted by your 2.0 uninstall. I could be wrong, but it’s a good idea to investigate this behavior.
In any case, for those following this post, the fix I’ve found so far is this:
1) Roll the computer to backup prior to updating PDFC.
2) Advise users to avoid PDFC updates.
3) Keep an older PDFC install .exe around for future installs.
4) Remind new users to avoid updating during install.
5) Study new PDFC documentation, audit other providers, pick a provider and rewrite the code from scratch.
Since this is not backward compatible with <2.0 versions, even a one-line fix is back to ground zero for developers. Deployment will be the same whether we use PDFC, Cute, Adobe or whatnot – rewrite the code and deploy a whole new PDF printing engine, along with whatever installs are required.
So we might as well take this time to reinvent and modernize our code, and see if PDFC and PDFF are still on top against their competitors, especially as PDFForge moves PDFCreator into the pay-for-use area. This is a whole different league than the open-source freeware that PDFC used to be.
Also, again I ask: If someone gets the new code to work, please post a snippet. I will do likewise.