I was in the middle of uploading a file when Direct FTP crashed, now it won't load properly. I can see just before it crashes that it is still loading old settings, even though I've tried many clean installs, trying to root out everywhere any hidden settings might be hiding but even after forensic deletion it is still somehow getting the old settings from somewhere which is presumably why it keeps crashing.

At the moment it is unusable, which is a shame because it's my favourite ftp client.

One thing you could try:
First, back up all your server connections, such as usernames, passwords, and server names.
Then, go into C:\Users\your-username\AppData\Roaming and find the file SharedSetting.ccs.
Move that file to a different location, e.g., the desktop

Afterwards, you can add your server settings again. Try first with one, preferably the most important one. If that works, you can add the other server details you may have.

You may even have to uninstall DFTP after having backed up the server connections and saved the SharingSettings.ccs. If so, reboot your machine before reinstalling the app.

If you get DFTP working again after the operations described, you can delete the old SharedSettings file. A new one will be generated when opening DFTP after a new install.

Sorry I didn't receive a notification that there had been a reply to this thread, although I am subscribed.

That is exactly what I was looking for - have deleted that file and re-added the sites. Thanks!