forticlient vpn Error find interface for local_gwy 0186d40a

Hello, 

I have more information, I have seen the following errors in the log:

31/01/2023 13:42:44 info sslvpn FortiSslvpn: 18720: fortissl_connect: device=ftvnic
31/01/2023 13:43:16 info sslvpn FortiSslvpn: 6836: PreferDtlsTunnel=1
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 2532: error: poll_send_ssl ->SSL_get_error(): 5, try:1
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 2532: error: poll_send_ssl -> WSAGetLastError():2746, try:1
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 2532: error: poll_send_ssl ->data size: 66, try:1
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 2532: [handle_driver_read_event]: error: poll_send
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 18308: error: poll_recv_ssl -> SSL_get_error(): 5
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 18308: error: poll_recv_ssl -> WSAGetLastError():2746
31/01/2023 13:43:19 info sslvpn FortiSslvpn: 18308: error: polling recv, try:1
31/01/2023 13:43:23 info sslvpn FortiSslvpn: 16164: Ras: connection to fortissl terminated

Have the same issue wit a Consultant PC Windows 11 7.0.7 and 7.2.0 Fre VPN Client. What I have seen or find out additionally. Firewall is not getting any Packet from the assigned IP Address. The internal DNS Servers are added but not the IP address we stay with 169.254.0.0. Adapter shows Network indentifying for ever because of missing IP Address. On Firewall side all looks good.

From another Post (Windows 11 22H2 update, FortiClient VPN doesn't work):

James Morales: I have been researching and digging into this for a while and stumbled on the solution you need to uninstall (KB2693643), just did it on my machine and FortiClient connected with no issue.

Former Post with workaround:

I have this same issue, the VPN connects just fine but the IP never updates and using the work around to manually configure the Network connections is the only way to get it to work.  There is no issue with the network, I have tried in numerous locations and it seems to be consistent with just the one PC with Windows 11.  Everyone else in the company has no issues connecting to the VPN.  Everything is configured properly so its not network, in an effort to try and figure out if its an issue with my profile I reinstalled windows 11 and the issue remains. 

In my case, the problem was an update to windows 11. To solve it I had no choice to reinstall the computer with windows 10, and everything worked again.

The problem in my case was a windows update. I had problems with several forticlient clients and all of them had the same problem.
I couldn't tell you specifically which windows update caused the problem, only that when I upgraded to windows 10, the computer worked without any problem.

I'm having the same issue here, been fighting with it all day. Interestingly though I have two identical builds (except specific device drivers) Both Win 11 22H2 and one connects and works fine the other doesn't.

With the failing machine I set a ping going to ping my DC. When I connected the SSL Vpn the ping replied for a few seconds then stopped. If I leave it connected it will on occasion reply. On a couple of occasions it would reply for a large period of time before failing again.

I've tried the following.

Disabled all IPv6 in all networking devices.

Re-installed Forticlient

Uninstalled and installed the VPN only version

Tried a different wifi connection

Uninstalled all windows updates

Uninstalled my RSAT tools

KB2693643 isn't installed on my machine so couldn't try that.

So now i'm facing the prospect of having to re-image the machine which I really don't want to do.

Checked the logs and I see the "Did not find interface for local_gwy 0786d40a" entry as well.

I would appreciate it if anyone has any further experience with this issue.

just to add something, I've done some further testing and although it wasn't that easy for me to do i managed to test it on a wired connection. On a wired connection the VPN is stable. So i'm leaning towards the Wifi driver. For the record its an Intel AX211

I thought I had but I had to do a re-image for an unrelated issue and now the problem is back, tried replicating my steps but it didn't work. Tried a different wireless device, still the same issue. I've noticed that if I run an RDP session as soon as it connects I can quite often get it to connect and then it will stay stable, despite not always being able to ping something over vpn. Very odd.

Errors like

Error find interface for local_gwy 0186d40a
Did not find interface for local_gwy 0786d40a

usually appear AFTER disconnect, and can be ignored in this case.

Per your later logs, real disconnect issue logged with following errors:

31/01/2023 13:43:19 error sslvpn FortiSslvpn: 18308: error: poll_recv_ssl -> SSL_get_error(): 5
31/01/2023 13:43:19 error sslvpn FortiSslvpn: 18308: error: poll_recv_ssl -> WSAGetLastError():2746

which mean Connection reset by peer.

https://community.fortinet.com/t5/FortiClient/Technical-Tip-Interpreting-WSAGetLastError-in-FortiClient-Debug/ta-p/191800

This mean Windows received reset packet - either from FortiGate, other network device, or other security software installed locally.