Random SSL VPN Disconnections on FortiGate 80E (Firmware 7.4.6 Build 2726 - Mature)

[AYBEYADMIN]

Dear Community,

We are currently experiencing intermittent disconnections for remote users connecting via SSL VPN on a FortiGate 80E running firmware version 7.4.6 Build 2726 (Mature). The FortiClient versions in use are 7.0.14.0585 and 7.4.2.1737, and the operating system is Windows 11 version 24H2 23100.3037.

Upon initial investigation, it appears that the disconnections tend to occur shortly after a download process begins. However, we have also observed random drops, even when the connection is idle, suggesting that the issue may not be related to download activity alone. It is also important to note that some users are not encountering this issue, indicating that the problem might be isolated to specific configurations or environments.

Has anyone encountered a similar issue with this firmware, FortiClient versions, and Windows 11? What could be the potential causes of these random disconnections? Are there any recommended configurations, best practices, or troubleshooting steps to help resolve this?

Your insights and suggestions would be greatly appreciated.

Thank you in advance for your assistance.

[AEK]

Hello Aybey

When it comes to FortiClient on Windows 11, I noticed the majority of issues reported in this forum are related to WiFi driver.

If you want to confirm this you may try connect via Ethernet instead of WiFi, just to confirm if it is related  to WiFi.

Then once confirmed, you may try change the driver of your WiFi adapter.

[AYBEYADMIN]

First of all, thank you for your response. In my opinion, the main issue seems to be caused by the Windows operating system. While I don’t experience any problems on my computer running Windows 11 23H2, I am facing this issue on company laptops running Windows 11 24H2. We had no problems until about a week and a half ago, but this issue has only recently started occurring. Do you think it could be related to the latest major Windows 11 update?

[AEK]

Yes it could be. Upgrading the WiFi driver, downgrading it or just changing it may help you fix the issue.

[peter-supply]

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