Multiple connections causes IP block on server.

Hi, using WinSCP V5.21.3 (just upgraded) and I have unticked the box on Preferences 'Use multiple connections for a single transfer' but am still getting blocked by my hosting company for 'too many connections' if I try to upload lots of folders/files, or try a search for files remotely.
What else can I do to reduce the number of connections created?

What protocol are you using?
Can you post a log of the session that caused the block?

Thanks Martin. Using FTP (to upload/download to a hosted WordPress site).
I think I've produced a log file (normal verbose?) attached.

You didn't post complete log. But anyway, it does not seem like you are using multiple (control) connections. Of course, there are separate data connections for each file transfer. But that's how FTP protocol works. If your provider is lame enough to block you for that, you will have to throttle your transfers. You might achieve that by limiting transfer speed in WinSCP:
https://winscp.net/eng/docs/ui_transfer_custom