last versions of forticlient vpn doesent'works

Hi, i have 7.0.8 saved from temp directory that work with all the ipsec vpn. the lastests version of the client doesen't works , tried on windows 10 and 11, many vpn tunnels... but nothing! i don' know how to resolve, i can't download old versions... so can someone suggest me another company that can provide a working vpn software?