I posted how I solved the problem which was sparked by the suggestion posted by user "thisemily" on this post
I am repeating it here below to spare you the extra click, although I hope you have solved your issues by now! ;)
I ran recently across the same problem and solved it by changing the PCI slot where the card was installed... it makes little sense to humans, but apparently make a world of difference to the PC hardware ;)
Assuming you had installed unsuccessfully both Card and Driver you have them (like I did) both on your PC. In such ase, the solution for me was as follows:
1) Turn Off PC
2) Remove the card from the current PCI slot
3) Turn PC back On and remove driver
4) Turn Off PC, remove power cord and wait a minute or two
5) Do not install card yet
6) Turn PC back On and install the driver
7) Turn Off PC remove power cord
8) Install the Wireless card in a different PCI slot THIS IS VERY IMPORTANT!!! Can't be the same slot as where it was installed before!!!
Note: If you have none available swap PCI slots or remove a PCI card to free up a different slot for the wireless card... remove a card you need the least and in its place install the Dlink Card. You may want to hold off on installing in a second step the card you have just removed, to be on the "safest" side.
9) Once the card is installed, Power up your PC
10) Once windows will be back up and running the hardware wizard should kick in and tell you that new hardware was found.
11) Follow the on-screen instructions
12) click "Continue Anyway" when XP will warn you that the driver hasn't been signed
13) Installation should be completed after you click Finish at the end of the New Hardware Wizard process
14) Simply go to your wireless networks and make sure all works in order
(I know that this process may sound a bit "anal" in some steps, but I was no longer willing to deal with any possibility of problems of any kind as I was ready to rip that wireless card to shreds!)
I hope this will help those who struggled with reviving an old PC to give to a friend!