that signal strength should be satisfactory for the wireless connection to work.
have you followed the installation instructions exactly?
first off - which port on the router did you plug the WAP into? did you use a regular cat5 cable (not a cross over). are you sure the cable is good.
next - did you run the setup program for your WAP on your office (hard wired to the network) computer-
you need to select an ssid (a word), and a channel (typically 6). when you setup your adapter card you have to enter the same values for these parameters.
select a wep setting (64, 128, 256 - beware! your adapter card must be set to the same level on encryption - the card may not support all the same levels as the WAP)
select a passphrase (must be exactly the same for the adapter card)
by the way - you may not be able to use wep if the adapter card is not linksys as well.
be sure the WAP is in access point mode (not bridging)
install and run setup on your adapter card - make sure all the values noted above are absolutely the same for the adapter card.
adapter card should be set to infrastructure mode
did you associate the appropriate protocols (tcp/ip) with the adapter card after you installed it?
did you run the internet access wizard.
finally, what operating system are you using in your office, what are you using in the house?