TLS session of data connection has not resumed

[SDG01]

I've recently run into an issue on a long standing ftp server getting this error: 450 TLS session of data connection has not resumed or the session does not match the control connection

This started happening on a Filezilla client install that had recently changed their external IP. The connection/settings were fine prior to this event, but now this IP can't connect and gets this error message. This is on a Windows Server 2012 R2.

This error seems to happen frequently enough from what I've found from others online, but I've found no single resolution outside of unchecking the "Require TLS session resumption..." which isn't the best option.

Is there a solution to this?

[botg]

Are you by chance using an extremely antique version of FileZilla Client?

[SDG01]

Are you by chance using an extremely antique version of FileZilla Client?

3.32.0

We had updated both the client and server software to see if this error would go away with no luck. We also generated a new cert, made sure everything is patched up, tried a few different settings, but no resolution yet, outside of turning this off.

EDIT: Does FileZilla store connection info in a cache file that we can dump by chance?

[botg]

There's no such cache file.

I can only think of one reason this happens if using the most recent version: There's a malicious piece of hardware or software sitting between the client and the server that breaks the end-to-end encryption. Make sure to remove all such fraudulent devices and programs.