How to deal with the UE4 launch bug.

Right-click on the game giving you the issue, go to launch options and paste in the following command.

cmd /c "set OPENSSL_ia32cap=:~0x20000000 && %command%"

This sets the OPENSSL_ia32cap environmental variable to ignore the Intel SHA Extensions on 10th Gen Processors and later, because Unreal Engine 4 (versions 4.13 through 4.21) contained an older buggy version of OpenSSL that causes the crash on 10th Gen and newer CPUs.

It doesn't open your system up to anything nefarious online, just prevents UE4 from trying to use the 10th Gen and later CPU SHA extensions, which triggers the bug and crashes the game.

By putting it into the Launch Options for the game, it will just change the variable for *that* game, and only while you're playing it, instead of setting the variable globally & permanently.

Source: Intel.
https://www.intel.com/content/www/us/en/developer/articles/troubleshooting/openssl-sha-crash-bug-requires-application-update.html

Hi, Allie!