Permission is, as usual, a double-edged sword. It happened when I tried to transfer files to a remote Linux server.

I created a directory on the remote server and attempting to transfer files via FTP client but got an access denied error. It is weird because I do login using the same account and thus as the owner of the directory.

The one that solves the problem in my case is by changing ownership of the folder recursively (-R option) and use name of the user as group name such as:

sudo chown -R <user>:<user> <directory>