I installed GNOME DE and the packages and Nautilus got updated to 3.6 but I don't like it.
I removed GNOME DE packages but Nautilus still remains at 3.6.
How can I revert back to 3.4?
I take it that you have installed Nautilus 3.6 from the GNOME 3 PPA. TO revert, you can just purge the PPA using ppa-purge . Run this command to purge the packages from GNOME 3 PPA and you would revert back to the default Nautilus 3.4.
Step 1: Kill Nautilus
Step 2: Install ppa-purge
Step 3: Purge Nautilus 3.6 repository
Step 4: Uninstall Nautilus 3.6
Step 5: Update apt repositories
Step 6: Install Nautilus 3.4