FortiClient won't connect using some Wi-fi networks

[tomoverton]

I have FortiClient 5.4.2.0860 on Windows 10 and it will not work when I try to use it through the Wifi at my local library (had this problem once before at a mall also). 

When using the library's Wifi, Forticlient gets to 10 percent and then says "Unable to establish the vpn connection. The vpn server may be unreachable".

I can establish a Forticlient connection through most other Wifi networks just fine (hotels, Starbucks, airports, etc).   

My company's VPN server is set up to listen using port 10443.  

I have tried disabling Windows 10 firewall and Windows Defender and it doesn't help.

Could the library's network be blocking port 10443?  

Thank you,

Tom

[ede_pfau · Accepted solution]

That's what I would suspect. Hard to tell without asking.

For a quick test (and a solid solution) you could move the SSLVPN port to 443 which will always work. If already in use you'd have to find a workaround.

[Logesh]

Hi Ede,

I have recently changed my Wifi network provider from BSNL to ACT.  I too faced the same issue with connecting forticlient VPN, as my company also use same 10443 port. As per your suggestion i have changed the port to 443 & tried connecting, it's show's same error. Is there any solution? Is there any possibilities that i can unblock 10443 from my ACT network (tp Link router) if yes please guide me.

Thanks in advance.

[Someguy55]

The Library/Hotel may have a web capture portal that requires you to accept a their terms of service before you can access their network. Did you try going to Google.com or something to verify you can get to the internet before trying to VPN to work? If so, and you could get to Google, I'd say they're blocking 10443. Especially since VPN worked elsewhere.

[tomoverton]

Someguy55 wrote:

Did you try going to Google.com or something to verify you can get to the internet before trying to VPN to work? If so, and you could get to Google, I'd say they're blocking 10443. Especially since VPN worked elsewhere.

Yes, internet works fine.  Only FortiClient doesn't work from this library's WiFi.  I guess this library has things pretty locked down, they only want you to access their online internet resources but not much else.  As Ede mentioned if the SSLVPN port was changed it would probably work but I don't have control over that, I'm stuck with the way my company has Fortinet set up to use 10443.