I'm running version 188.8.131.521 It seems when I log back into my computer after walking a way for a bit the network connections have issues for a minute or so and get certificate errors with Skype for Business and web pages will show non compliance message. After a few minutes things go back to normal.
Quoting from Chapter 7 in the book "UTM Security with Fortinet: Mastering FortiOS" By Kenneth Tam, Martín H. Hoz Salvador, Ken McAlpine, Rick Basile, Bruce Matsugu, Josh Mo:
If the Forticlient keep-alive message is not received when it is expected by the Fortigate, such as when the endpoint was shut down or put into a sleep mode, the endpoint information is stored for the duration of the compliance timeout idle time, after which its authentication entry is removed and any subsequent traffic from that endpoint IP address is blocked until a new endpoint compliancy check can be performed.
I think, this is also applicable to other VPN clients like Cisco anyconnect where the VPN host closes the connection because it can't renegotiate the session key.
However, try changing the Network Connections settings under Power & Sleep to "Never" in Windows 10 once and see if that helps.
Any update on this issue? I still have this problem on ubuntu version 6.4. every time the computer go to sleep, i need to restart manually. Isn't there any health check to restart it automatically? The Kerio VPN client did not have this issue.
It looks like the issues reported by OP is different. I think he had problem with SSL VPN connections. He stated that FortiClient requires a system reboot to connect successfully, if the computer had gone to sleep while VPN tunnel was up. This is my understanding. Such issue is known to exist in FortiClient 5.4.
This issue is still in play as described in the OP's post. I am running Windows 10 on a Lenovo X1, the Forticlient version is 6.0.0.0067. Additionally the tray icon drop down menu is not available when the issue is in play and even opening up the client and connecting manually doesn't work. Due to the lack of a drop down from teh tray icon it is also not possible to quit the client, stopping the SSL VPN daemon process however corrects the issue.
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