The crash was reproducible on my workstation as well:
Windows 10.0.19044
FortiClient 7.0.5.0238
In my case, if the Siemens SIMATIC Automation Tool is installed, the crash becomes reproducible. https://support.industry.siemens.com/cs/de/en/view/98161300
Only a complete reinstall of Windows (including everything) was the solution - until now. (tool uninstall, reg. entry resets etc. did not help) According to a Siemens-forum, tweaking the registry might help, but did not in my case. Finally this comment solved my issue: https://support.industry.siemens.com/forum/us/en/posts/tia-portal-v17-conflict-with-vpn/262291/?page=0&pageSize=10#pagetop:~:text=7/20-,/,-2021%201%3A42
In case the added FortiClient NIC adapters have active usage of the SIMATIC Industrial Ethernet (ISO) protocol, at ca. 98% connection status Windows will crash because of an exception in ndis.sys. Solution: see Control Panel --> Network and Sharing Center --> Change adapter settings --> select a FortiClient adapter --> uncheck the entries for special protocol(s), in my case the "SIMATIC Industrial Ethernet (ISO)"
There might be other applications that utilize NIC management and couple a protocol usage to it, which may be a rare but recurring issue in some corporate environments. In case special protocols are in use, activate them only on a separate physical network interface (e.g. USB NIC) to avoid this issue and keep using special industrial applications.