FortiClient 5.4.0 use digital signing SHA-2 and for Windows 7 SP1 and Windows XP you need install this update.
Info from Forticlient Release notes:
Installing on Windows 7 and Windows XPFortiClient 5.4.0 files and drivers are digitally signed using SHA2 certificates. Microsoft Windows 7 and Windows XP are both known to have issues with the verification of SHA2 certificates. Ensure your Windows system software updates are up-to-date before installing FortiClient 5.4.0 on either of these two platforms.
I have the same issue. When trying to install patch windows says the patch is no longer suitable for this machine. As in the patch has already been installed.
To clarify, I try to install the client 5.4 on a windows 7 pro x64. The client says need kb3033929 to be installed. I download and install the patch. The patch says that the patch is no loner suitable for this machine. I look up logs it shows that the patch is already installed.
Was able to install Forticlient 5.6 on Windows 7 pro x64 sp1 traditional chinese. However when trying to install the same client on Windows 7 pro x64 sp1 simplfied chinese, have same message cannot install unless kb3033929 patch is installed. When checking logs and installed patches it shows that the patch has already been installed. Tried manually installing the patch the patch says the patch is unsuitable for this computer. Tried using both the automatic installer, and the offline installer.
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