Yes, that's the base, where i started. And yes, the proxy settings where added to the open script, but this didn't help. I'l try it a little more, when i have more time.
For now, i must give up to use the script. But maybe I'll try it later again.
opencommand and removed slash in
open davs://user:firstname.lastname@example.org/dav/files/ -rawsettings CacheDirectories=0 CacheDirectoryChanges=0
/log=path_to_log_filecommand-line argument. Submit the log with your post as an attachment. Note that passwords and passphrases not stored in the log. You may want to remove other data you consider sensitive though, such as host names, IP addresses, account names or file names (unless they are relevant to the problem). If you do not want to post the log publicly, you can mark the attachment as private.
open davs://user:email@example.com/dav/files -rawsettings CacheDirectories=0 CacheDirectoryChanges=0
put test.txt /
"c:\Program Files (x86)\WinSCP\winscp.exe" /log=c:\tmp\script.log /ini=nul /script=c:\tmp\script.txt