If you've left a shared folder, you can add it back to your Dropbox on dropbox.com.

Add a shared folder you left

1. Sign in to dropbox.com.
2. Click Sharing in the sidebar on the left.
3. In the Folders you can add to your Dropbox section, find the folder you left.
4. Click Add beside the folder name.

Dropbox will automatically download the shared folder again, even if a previous version of it still exists on your computer. If the previous version is in the same location, Dropbox will download the new version of the shared folder and append "(1)" to the end of the name (so that you don't have two folders with the same name).

If you'd like to change or restore the previous name, you can rename it to whatever you'd like.