IPsec VPN issues with Pre-shared key

[pantalaimon]

Hello everyone,

I am in my first year of an IT degree, I am very new to all this. For our programming course, we use the university's coding environment, to use it we have to connect to the university VPN.

The university uses Forticlient, we have to follow an instruction document explaining how to download Forticlient and change the configuration settings.

This has always worked for me, I was able to access the uni's VPN just fine for months, now suddenly there have been some issues. It won't let me in, so I tried all kinds of things, I tried changing my uni password (because we use our uni credentials to log in to the VPN), which didn't work. I tried uninstalling and re-installing forticlient, which didn't work. I tried re-entering all the configuration settings over and over, still I had the same issue.

Then I noticed that when I save and exit the configuration settings, and then re-open them, the pre-shared key is different, it's longer, forticlient seems to be automatically changing the pre-shared key upon saving.

I don't understand why it's doing this and I have absolutely no idea how to fix it. Does anyone know how to solve this issue? Any help would be greatly appreciated.

Thank you :)

[rosatechnocrat]

Pre-Shared key is not changed, instead after you input it shows hidden and longer only. 

In this case the only method for you is to contact your Network / IT Firewall Team. Because all the configurations are based on Fortigate Firewall configuration. Nothing can be done From forticlient side. Forticlient can not do anything to sort this. COntact your IT team to get the right details or right reason why your facing this. 

[Magnitude_8]

I don't think the issue is with the pre-shared key. If you save and re-open the connection the key is obscured (replaced with 20 dots) so that an unauthorized user cannot infer the key length, but the key you entered is still used unless you change it.

If possible, test with another device, otherwise you probably need to seek support from your university.

[celeriactrain]

Hi!
This sounds frustrating, but don’t worry — the issue is most likely not with your password or with FortiClient itself. When FortiClient “changes” the pre-shared key after saving, it’s not actually replacing it — it’s simply masking it with a longer placeholder (for security). So the key isn’t the problem.

What usually causes this sudden connection failure is one of these:

The university changed the VPN configuration (IP, authentication type, group name, certificate, etc.) and the instruction document is now outdated.

Your VPN profile is no longer authorized — sometimes universities reset VPN permissions each semester or after password changes.

Two-factor login is now required and your profile still uses pre-shared key only.

Windows / macOS update blocked the old FortiClient version, so it needs an update to match server settings.

A few things you can try:

✔ Check if the university released a new VPN instruction PDF or new connection server name.
✔ Ask IT support to re-enable VPN access on your student account (this solves the problem for many students).
✔ If FortiClient is old, uninstall it fully and install the latest version directly from Fortinet or from the university portal.
✔ If the university recently switched to SSL-VPN instead of IPsec, you’ll need a new connection profile.

Since the VPN wheelie life worked fine for months and suddenly stopped, it’s very likely a server -side change rather than something you did wrong. Contact IT support with a screenshot of the error message, and they should be able to confirm whether your account or configuration needs updating.