SFTP / SSH issue

After a recent update I found that SFTP and SSH had stopped working when I tried to connect from my windows laptop.
Putty showed an error “couldn’t agree an exchange algorithm”. Upgrading Putty fixed this issue and restored SSH but I use SFTP within a product called “Beyond Compare” for syncing files and this refuses to connect now.
I don’t have an upgrade for this so was wondering if anyone can tell me what has changed and if there is a workaround?

I would recommend contacting the developer of this application.
You could also edit /etc/ssh/sshd_config to downgrade ciphers; but this is not recommended.

Thanks Sam.