|You restored (recovered ) the laptop in the house Let's call it "A"and now it's the only one that can see your D-link over wifi? The tablets and the other laptop (let's call it "B") in the garage can't see even the extender; let alone the main router?|
If you bring the tablets and laptop B into the range (into the house) of the D-link main router; do they see it then over wifi?
Does laptop B connect to the main router OK via cat-5?
Connect laptop A to your D-link via cat-5; access and view the wifi settings for the main (D-link) router; note them down.
Check what security levels/measures you have invoked (if any)..Is the router broadcasting its SSID? Is there "mac filtering" invoked - this means allow only these listed mac addresses access, or disallow these listed mac addresses access; or allow anyone access (mac filtering is not invoked).