How do I create sub-folders (nested folders) in Thunderbird?

Subfolders (nested folders) allow you to organize your mailboxes in multiple levels of folders. This can be helpful in sorting and managing large numbers of mailboxes.

When you use the New Folder... command in Thunderbird, by default it creates an actual mailbox within your IMAP folder or your Local Folders. You cannot add a subfolder to a mailbox.

To nest folders within your IMAP directory on the server:

How do I start Firefox or Thunderbird when it is stating that my 'profile is in use'?

With Netscape:

rm $HOME/.netscape/lock


rm ~/.netscape/lock

For Mozilla:

rm $HOME/.mozilla/*/*/lock


rm ~/.mozilla/*/*/lock

For Firefox:

rm $HOME/.mozilla/firefox/*/lock
rm $HOME/.mozilla/firefox/*/.parentlock


rm ~/.mozilla/firefox/*/lock
rm ~/.mozilla/firefox/*/.parentlock

For Thunderbird:

rm $HOME/.thunderbird/*/lock
rm $HOME/.thunderbird/*/.parentlock