Solved! Lenovo Laptop won't pick up wifi connection

If the laptop can see other WiFi networks, just not this one, and this particular WiFi network is a 5 GHz network, then you've probably run into a problem caused by DFS. The fix is easy: Go into the router settings and change its 5 GHz channel from Auto to something between 36-48 or 149-165.

Shortly after the FCC opened up the 5 GHz band, it was discovered that some of the frequencies were useful for a new type of doppler weather radar. This radar is very useful at airports which frequently suffer bad weather, and is easily interfered with by WiFi broadcasts on those frequencies. So the FCC took the unusual step of placing new restrictions on the open 5 GHz band. WiFi devices are still allowed to use the 5 GHz band, but if they use the frequencies which could interfere with radar (channels 52-144), they have to comply with DFS - dynamic frequency selection. The router has to monitor for weather radar, and automatically switch to a different frequency (channel) if it detects radar in use.

Some WiFi device manufacturers did just that. Some took the lazy way out and simply blocked their device from ever using channels 52-144. The situation you're experiencing can happen when your WiFi router is the first type of device and randomly picks a channel between 52-144, and your laptop's WiFi card is the second type of device and is blocked from seeing anything on channels 52-144. The fix is to prevent your router from using channels 52-144.