Important Heartbleed information
As of April 2014, all older builds have been removed as they were built on OpenVPN 2.3.2 as a base. This version of OpenVPN for Windows used an OpenSSL version vulnerable to Heartbleed.
If you downloaded a release based on 2.3.2, you should obtain version 2.3.3 of OpenVPN that contains a newer OpenSSL, and includes the TLS 1.2 negotiation features one of my earlier preview builds did.
List of Releases and Features
See the Releases wiki page here for details on what each particular build set contains.
Releases here are generally based on a specific official release with a particular set of changes. These "early feature previews" allow early adopters and testers to try them out ahead of time.
This means these downloads are effectively "unofficial betas." The intent is to provide a testing ground for new features before they appear in an official release; compatibility checking and feature testing are the intended benefits.
Building for Windows has always been a bit of a black-art, and while OpenVPN has fairly good build documentation, it effectively requires a build environment that can be daunting for those not familiar with the nuances. The installers here allow features not yet in an official release to be used on Windows without needing to build them manually.
The builds I release here will start with a build number 600 and be incremented as makes sense; future builds of the same feature will increment this number. Consult the buildinfo text file on the download page for specific component versions used in the build.
Since I build these myself, any modified or re-packaged components will not have the upstream Microsoft Authenticode signature. I do sign all my builds with GPG, and you can verify them with my public key, ID 0x606FD463.
Getting help with these releases
If you have an issue with a particular release preview here, the best place to bring this up is on the OpenVPN Users mailing list, firstname.lastname@example.org.
The releases found here are based on official releases with some more recent source code modifications, so it will be best to note if your problem exists with a preview version specifically (and thus not with the official release,) and what exactly you are trying to do. Be sure to note what release here you are using, and ideally link back to the Releases wiki page for clarity.