OpenVPN Support Forum

Hi
Tried the new version 2.5.4 which came out today (05Oct21) found that we get an error about "no openssl_applink" and the connection stops.
Reverted back to version 2.5.3 (17June21) and the connection/vpn works as expected.
Install was for 64bit windows.

Is this expected behaviour for this new version?

Cheers

Please give the exact version of Windows you are using.

Exact version unknown as I had to work it all out via a teams based remote session. As it was a new install for our lovely IT I suspect it will be latest enterprise edition.

Same problem here on three different clients.
Windows 10, 21H1

Same problem. Windows Server 2012 R2, all updates.
cipher BF-CBC do not work with "no openssl_applink", cipher CHACHA20-POLY1305 work fine. Windows Server 2008 R2 — all ciphers works.

Is this a config with pkcs12 in it? This seems to trigger some new surprises in OpenSSL if built with vcpkg - and none of our test cases today (on windows) use pkcs12 based anythings, so that did not get caught.

cron2 wrote: ↑

Wed Oct 06, 2021 6:11 am

Is this a config with pkcs12 in it?

Yes

cron2 wrote: ↑

Wed Oct 06, 2021 6:11 am

Is this a config with pkcs12 in it?

Yes.

Same problem here with Windows 21H2 and all the updates. I'm using cipher AES-256-GCM. Reverted to 2.5.3

So, found the issue. It is related to MSVC builds of 2.5.4 and "--pkcs12" in use in the openvpn config (which was not explicitly tested since nothing in the pkcs12 support in openvpn has changed since a very long time - but on windows, with MSVC builds, some special care needs to be taken).

We'll have a new 2.5.4 installer with a bugfix for this constellation out later today (if everything goes as planned).

Just installed "OpenVPN-2.5.4-I602-amd64.msi" and the VPN connects again. Thx!