My laptop was so slow that there was no choice but to do a factory reset or restore. The operating system is Windows 7 Home Premium OEM pre-installed and therefore, was asked to reinstall Windows 7 Home Premium from the partition using recovery.
First reaction was panic. Could not find how to do it. Next I looked up Microsoft where it said if no OEM CDs were provided or were corrupted I could use their supplemental parts programme to get Installation CDs for free. Felt lucky, but found that it was only for US customers.
Finally, googling around got me to this link https://in.answers.yahoo.com/question/index?qid=20110530094510AABjeSD where it said press R or F11 and power on the laptop to boot. Select the Windows 7 option that appears on the screen.
Next chose Advanced Options for Windows 7 and select the Repair Your Computer option and press Enter to start recovery. When in System Recovery Options, enter a user name and a password, then selected to completely remove all data and reinstall or leave my data intact. As I suspected malware, I chose to do a full reinstall. Now the installation started.
At some point I got this error. Error message “The Computer Restarted unexpectedly or encountered an unexpected error” after System Startup on Windows 7 Recovery
Again googling got me to this link http://answers.microsoft.com/en-us/windows/forum/windows_7-system/error-message-the-computer-restarted-unexpectedly/b770f14d-e345-e011-90b6-1cc1de79d2e2
Instructions to overcome the error message were followed where I pressed Shift+F10 to get to a command window. Entered
to open the Windows registry and
Look for a variable that says setup.exe. Changed the value from 1 to 3.
Closed the registry window and the command window and clicked OK. The installation continued after a restart and was completed successfully.