i just purchased a TTonexl and when i hooked it uyp to our car my position was off by about a block. now i've read that make sure unit has the latest software updates installed, so i used the disc that came with the unit and installed tthome version 1. ? ? ? whatever, it then checks for update and shows the update as 7. ? ? whatever. it asks to install update now...i say "yes" then it says to make backup...which i did.\r\nafter backup is made i select install to tomtom and it comes up with an error " an error occured while unpacking compressed file"" . i try get update again...once it downloads i select it to install and same error message?\r\nalso another screen popped up once to upgrade tthome to version 2.? ? ? whatever, i said ok... it deleted first version and about half way through it gave a "CRC error that install shield will have to abort. \r\n\r\n i am running windows xp , sounds like maybe a puter prob to me? or can anyone shed some light regarding the errors?\r\n\r\nthanks in advance!