Help finding network

Hi there, I have been at the same location, with the same internet connection for over 3 years. I used my laptop for 2 years with the same connection with no problems. When I started having issues with my computer, I started using my roommates laptop. After restoring my computer (Toshiba), I was able to use it for a few days, and then I set it aside (was operating slowly), for about a week. When I tried using it again, I could not find my network. I am able to connect to the network on all other computers in the apartment. I have a list of networks that appear when I try to connect so it is picking up other networks in the areas. When i tried to add it manually, it tells me that the network already exists but I can't find it. What else can I do?? If more information is needed, please let me know. Thanks for the help!!

After restoring, I have been able to find the network, and then get the "Windows cannot connect to ___" message. "Wireless associate failed because Windows did not receive any response from the wireless router or access point." When I click to troubleshoot and try to locate the network again, I cant.