Hi, I'm currently using Lenovo Z580 Laptop which had a Pre-installed Genuine Windows 7 Home Basic OS when I bought it in September, 2012. But, I have upgraded it to Windows 8 PRO online using my internet connection on its launching date. But from near about 30 days ago, I'm experiencing an unexpected problem taking the WiFi Connectivity. After connecting to my WiFi, generated by my D-Link DIR-615 Wireless N300 Router with the mixed type broadcasting 802.11b/g/n the pinging reply from my ISP's IP (For me, it's 172.24.1.1) was just being seemed to be abnormal to me. The pinging reply used to show about 6ms, 2ms, 3ms response time but suddenly it transformed into 12 - 15 Request Timed Out constantly. Or, sometimes, it used to to display 3 to 8 Request Timed Out dialogue just after showing 2 to 3 short response times like mentioned before! Another problem is that, even if I get fixed and steady replies from my ISP's server, Firefox sometimes doesn't respond properly. I'm currently using FireFTP to transfer files between my Lappy and FTP Servers. But, sometimes after uploading a few MBs of a file, transmission stops and even I also can not browse web then. But, still then I can see the response time in PING nearly about 2ms to 4ms with great steadiness! But, in order to browse again, I had to disconnect and Reconnect to the WiFi again. Now, I'm also facing another problem. After connecting to my WiFi, it's also displaying Reply From: 192.168.0.1: Destination Host Unreachable after 2 to 3 minutes of successful pinging replies from my ISP's hosting IP: 172.24.1.1. 192.168.0.1 is my Router's IP and by putting this IP I can visit my router's configuration home page. Some days before such critical faults were noted, I also found some abnormal behavior from my Lappy's WiFi. It used to show the Connected WiFi icon in the Lock Screen just after the completion of Booting (Even before signing in to my Local Account). And, normally I then used to sign in and go to desktop from the start screen. My Kaspersky Internet Security 2013 always takes too much time to launch and usually activates its protection after the start ups of all the auto start apps. But, after a few minutes, my WiFi used to get disconnected automatically! If, I try to reconnect, then it shows Unable to connect dialogue! After performing these steps again and again, it even used to stop displaying the SSID of the WiFi Signal! Then I had to go the the Adapter Settings and then disable and re-enable the WiFi Adapter. I'm still facing all of these problems even on today! Please help me. Thanks.