Airport express not seen by my XP computer

Question

I have two Airport Express that in the past have worked great!
Recently we moved and in reestablishing the home network, with the same router and computers, now the network does not recognize either AE.
I have tried locating it both wireless and hard-wired to the router. The Airport Admin Utility...used previously to configure the AEs...doesn't see them in either scenario. I have tried a hard reset and turning off all known firewalls....and that doesn't seem to work either.
Everything else about the network seems to be working (Desktop, and two laptops, print server, routers, etc.)
Any ideas?

Answer 1

One of the problems with WEP is that the actual standard relies on a 10 character HEX key for 40bit WEP and a 26 character HEX key for 128bit WEP.
In order to make things easier for people, vendors use certain algorithms to convert simple alphanumeric passwords (or passphrases) into HEX keys, thus enabling people to use simple memorable WEP password rather than lengthy HEX keys.
The problem is that different vendors use different algorithms to generate the HEX key and therefore a ASCII password on an AEBS will be hashed differently on a Netgear client and vice versa.
One thing is a 13 character 128 bit WEP password will be hashed by all vendors in the same way (if you use 40bit WEP then a 5 character password is required).
Though sometimes not even that works and the HEX key must be used regardless.
AirPort: Joining an encrypted wireless network
http://docs.info.apple.com/article.html?artnum=106424
Choosing a password for networks that use Wired Equivalent Privacy (WEP)
http://docs.info.apple.com/article.html?artnum=108058
iFelix