Windows
VPN connection failed because the SSL certificate on the firewall expired
VPN access failed because the public-facing SSL certificate on the firewall had expired. Installing the replacement SSL certificate resolved the connection issue and the user was able to connect again.
Killed once by someone from XL.net, on 2026-04-28.
Affects
Versions
- Windows
Hardware
- Firewall
What you see
- Cannot connect to the VPN.
Why it happens
Likely The VPN's public-facing SSL certificate on the firewall had expired.
When it shows up
A Windows computer cannot connect to VPN and the VPN gateway is using an expired public SSL certificate on the firewall.
You are in this case if:
- The firewall's public SSL certificate is expired.
- VPN connection attempts fail until the certificate is renewed.
1 fix below
The steps that killed it
The steps are behind a quick check
There are two ways in and both take a few seconds. Signing in opens the steps on every bug page; so does reading the picture.
Or answer this
Drawing a picture for you.
Can't read it? Sign in instead.
Keeping it away
- Monitor the expiry date of the firewall's public SSL certificate so it can be replaced before it expires.
Someone from XL.net killed this on a Windows computer on 2026-04-28. It is written up from that one repair, so it cites no outside page.