Easy. Your unspecified wireless card and unspecified wireless router are having some disagreement as to the WEP key or WPA phrase. Some cards and routers insist that the ASCII WEP keys be exactly 5 characters long for 64bit and 13 characters long for 128bit encryption. If you make them longer, the stupid firmware will sometimes just truncate the key to 5/13 characters. If you still have problems obtaining a common encryption key, try a hexadecimal encryption key of 10 or 26 characters. That's sure to work.