The mysterious slot can accept a wireless network card or a modem card, if the laptop doesn't have one or the other, or possibly to substitute for the original internal component if it has failed. Laptops were often supplied with a plastic dummy card to keep the slot and internal contacts clean. 
Here's a photo of one - 
http://www.barcodetraders.com/ois/ois_images/symbol_s24_hr11mb_wla.jpg
Paul Hachmeyer

-----Original Message-----
From: Personal Computer Hardware discussion List [mailto:[log in to unmask]] On Behalf Of cubbettee cubbettee
Sent: Saturday, September 26, 2015 12:51 PM
To: [log in to unmask]
Subject: [PCBUILD] network cable

Would you believe now works, 2 independent jack with cords did not but the third did.I also installed from everything possible from right clicking  on the lan and getting the local area  and installing all those items,  some of which I am sure or no longer really used. 
Now I don't know if I have a wireless card in there though I set the drivers and of course there is this slot on the side--not sure what it is with a plastic thing the size of a credit card you can pop out--maybe a pc slot?                                         
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                          PCSOFT's List Owners:
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