My input:
http://www.example.com/New file.zip
When try to download a remote file that have space in its url aria2 complains about it:
Exception caught
Exception: [download_helper.cc:451] errorCode=1 Unrecognized URI or unsupported protocol: New
Try to change the space into "%20"
aria2c http://www.example.com/New%20file.zip
Or
aria2c "http://www.example.com/New file.zip"