I should add that it is also possible that ISPs may be blocking ports... So, check around with your friends who may be using the same ISP...
Workaround taken from *forums.afterdawn.com/thread_view.cfm/10/66716
A lot of ISP's are blocking the emule default ports (4662 and 4672).
HERE IS MY FIX: First, change the two (default) ports in eMule to something other than 4662/4672 (mine are TCP:4660 and UDP:4670 -> (Close eMule). Second, (important) change all ports: WindowsXP Gateway, Winxp_firewall, and router and anyting else you are using (i opened all using the new ports just in case). Make sure you save settings in the router.
Finally, open eMule. mine connected almost instantly and running at HIGH ID.
Arun
EDIT: Okay, I have checked the above with my system and it appears to be the case here for me (touchtel is my ISP). I changed my eMule ports to 5555 for TCP and 6666 for UDP and set Kerio to allow data for emule and I got High ID (I checked first with default ports and got Low ID).