Permission denied when downloading with transmission daemon

Assuming the path to the download folder is /home/chen/TV shows, run the following:

• add chen to the debian-transmission group

  sudo usermod -a -G debian-transmission chen
  

• change the folder ownership

  sudo chgrp debian-transmission /home/chen/TV\ shows
  

• grant write access to the group

  sudo chmod 770 /home/chen/TV\ shows
  

• Stop the deamon with

  sudo service transmission-daemon stop
  

• The last thing to do is change the file creation mask, so that the downloaded files would be writeable by chen.

  sudo nano /etc/transmission-daemon/settings.json
  

  … and change "umask": 18 to "umask": 2. Hit Ctrl+O to save and Ctrl+X to exit.

Start the daemon with

sudo service transmission-daemon start

This is a permission issue based on the user ID that is running Transmission. Transmission sets up a default user that you might not expect on first install. The user name is debian-transmission.

I will explain how to change that:

1. Stop the Transmission daemon sudo service transmission-daemon stop
2. Open the Transmission config file for editing: sudo nano /etc/init.d/transmission-daemon
3. Find the line that says USER=debian-transmission and change it to the user that owns the folder in question. If you are not concerned about security issues, you can also use USER=root in this file. (Not advised, but good for troubleshooting).
4. Alternatively (instead of point number 3), modify the /etc/fstab folder to mount the folder with correct permissions for the user that runs the transmission-daemon.
5. Start the Transmission daemon sudo service transmission-daemon start

Check if you're using an "incomplete" folder. The error can be misleading in this case and it may be the incomplete folder you do not have write access to.