I m using Acer aspire E1 series with 500GB hard disk and 6GB RAM. My laptop suddenly started working slow as if 7-10 mins to boot the screen and then hang to open Chrome browser or play youtube. I put system on hibernation and next day,it started to show ctrl + alt+ del for read disk error. SO i decided to format the system. Now, i have re-installed windows 7 for 3 times and always screen is hanging at Completing Installation. i really dont know what to do. I have deleted all the partition and all. Still the issue Persists Please help me here.