I know its been answered that you need to change the URL in the acp and restart the server.
However I do not have the power to reset the server since I use a shared hosting plan. How do I go about on going into a different directory without having to do that? I checked the FAQ and that didn't seem to help.
The one specific situation I am aware of that requires a restart is when you are running APC opcode cache and that cache fails to update after moving the files. The nature of the problem means you will immediately see fatal errors on all forum pages after the move, so it will be obvious if this problem exists.