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New Contributor

No VPN connection after upgrading to Windows 10 2004

Hi all,

in my company we're using fortigate for VPN connections (SSL-VPN) (v6.2.3).

everything worked fine up to yesterday with Windows 10 (1909).

Today i upgraded Windows 10 from 1909 to 2004 on my machine. After upgrade was finished I tried to log in by Forticlient (

After typing in username, passwort and smardcard-code the process rised up to 80 percent and an error prompt:

"The Server you want to connect to requests identification, please choose a certificate and try again (-12)"

So i deleted the smartcard, created a new one and installed a new certificate.

After that there was a new error prompt:

"Unable to logon to the server. Your user name or password may not be configured properly for this connection. (-12)"

But i not changed my access data (and it worked yesterday).

There is no solution to fix it, i found in several community forums.

I changed my password to one without special characters, I reinstalled forticlient on my computer, i created a new smartcard, i tested it on another computer with the same OS, but there was always the same result.

Any ideas?



New Contributor

Hi Tickforti, did you already have a fix for this? i do have the same problem we connect with a client certificate. When i disable SSL TLS 1.2 in IE the connection works again but then a lot of websites do not work anymore.


I hope Forti comes with a fix soon.


Kind regards,



Hi Marco,

i have no fix for this problem, if i disable SSL TLS 1.2 in IE its not working as well on my devices.

We tried to figure out this probem with normal fortinet support and forticlient support. Forticlient support told us, a virtual smartcard is not supported and we have to ask microsoft support...

But by now, we have no solution


Kind Regards,


New Contributor

Hi Tickforti,


Did Microsoft Support offerd you a solution? 

We have a similar setup, and we can't get it fixed.


kind Regards,


New Contributor III

Has anyone found a solution for this or can confirm the legitimacy of the issue? Out of 3,000K clients, we only have one customer complaining about it.
New Contributor

Hey, have you managed to resolve this? I am having the exact same issue upgrading from 1909 to 20H2


The issue I have is on a particular hardware model (HP Elitebook G3).


Upgrading to 21H1 exhibits the same issue. New builds also see the issue. 


I'm about to raise a ticket with M$ but expect this will be very difficult to get traction on.

New Contributor III

I ran into this and what worked was two things:

1) for some reason i had to re-enter the username in the (saved) VPN client settings. Even though it displayed properly, i had to manually retype it in.

2) I lost DNS name resolution for the remote gateway name. I changed the remote gateway address to IP and haven't had a problem in over a year.

Really dumb problem - hope it helps someone.

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