Ok what exactly does the error message say in English? I tried running it through a scanner into text and then translating but can’t get it to make any sense.
And just to double check, this is so your friend can hit this externally from your network? If so why not just have them log into the dashboard and and download through the web interface? I know it’s not as seem less as FTP.
Also, depending on your setup, why not drag the files over to another system on your network that might already have an FTP setup? Personally I don’t like anyone having access to my Deluge box, because I don’t know how to monitor or lock down Linux. I have a file share setup on my Deluge server, copy the files over from my box to my Windows file server, then have a front end for users to download from there.
 yes I know but I kind having things also like this because to me it seems more straight forward, and I repurpose ahold hardware to make up my network. Plus my Deluge server is on my local LAN not a hosted server