like many other users, after upgrade to windows 10 , i found my kaspersky security was not there, all other apps were working fine, as a normal user i searched all over internet , and i found that 3rd party antiviruses may not work in windows 10, i tried to download latest version from kaspersky.com, but didn’t worked.
but i found one news from Microsoft, if we have active subscription of a 3rd party antivirus, then after installation windows 10 will automatically install the compatible version of that security software,
after few restarts i got notification that kaspersky internet security have a new version click to download, i downloaded and it installed automatically,
after that again asked for a restart and i did,
surprise my security software is working fine in windows 10 , just need to reactivate it using your license code,

here is screenshot as proof

Kaspersky working in windows 10