Normally, WEP key is set using a combination of 10 hexadecimal digit. Users normally save the key permanantly as a default setting. Combination of hexadecimal key is hard hard to remember. For instance try to remember this combination 1A4D5F9A01... it is hard right !
Let say you forgot your WEP key, how to recover it back ? You can retrieve your WEP without reset the wifi router. You can give a try to this free ware utility which is able to recover your wireless key from your system.
I don't know how many of you maintain a database of small utility but i always keep a database of small utilities because these utilities comes handy once in a while but at the time when you need them the most
you can download the WirelessKeyViewer from the below given link