Error Connecting to pfSense 2.3 using Putty

I forgot got the error and simply updating your "putty.exe" to the latest fixed the problem. Here are some pointers as well:

"Couldn't agree a key exchange algorithm (available: curve25519-sha256@libssh.org"

• Firewall rule(s)
• NAT/port forward rule(s)
• Gateway - well, quite far but I was doing a port forward of RDP for several hours that my target host gateway uses a different firewall :(

I'll update this post once I get to remember what particular error I encountered.