It turns out that OpenSSL 1.1.x uses API calls that are only available on Windows 7 onwards, which means that the latest beta will not run on Windows XP/Vista. At this point, the number of XP/Vista users is so small that I am not sure maintaining support for them makes sense. I am looking into whether 1.1.x can be compiled so that it will work on them but if it turns out that this is not possible, the next version of mIRC will be dropping XP/Vista support.
Update: I found a way to compile OpenSSL to avoid APIs that XP does not support. This change will be in the next beta.
Last edited by Khaled; 16/05/19 06:09 PM.