SMTP settings have stoped working

I verified all settings with my email host - they are correct. We also added Jotform IP Addresses to the whitelist, but I am still not able to get the addresses to authenticate.

I'm getting error that

SMTP Error: Could not connect to SMTP host. Connection failed. stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages: error:0A00018A:SSL routines::dh key too small

Hi twobostons,

Thanks for reaching out to Jotform Support. The primary reason for the error “SSL operation failed with code 1. OpenSSL Error messages: error:0A00018A:SSL routines::dh key too small” is that the Diffie-Hellman key size used during the SSL handshake is considered too small and insecure by the OpenSSL library.

This typically means that the server is using outdated or weak cryptographic parameters that do not meet current security standards. Updating the Diffie-Hellman key size to a larger, more secure value (e.g., 2048 bits) resolves this issue.

Reach out again if you have any other questions.