Follow these instructions to start Windows 7 in Safe mode.
1.Turn on or restart your PC.
2.Just before the Windows 7 splash screen appears, press the F8 key to enter Advanced Boot Options.
3.You should now see the Advanced Boot Options screen. If not, you may have missed the short window of opportunity to press F8 in the previous step and Windows 7 is probably now continuing to boot normally, assuming it's able to. If this is the case, just restart your computer and try pressing F8 again.
4.Once you're in the Advanced Boot Options, you are presented with three variations of Windows 7 Safe Mode you can enter. Using the arrow keys on your keyboard, highlight either Safe Mode, Safe Mode with Networking, or Safe Mode with Command Prompt and press Enter.
Safe Mode: This is the default option and is usually the best choice. This mode will load only the absolute minimum processes necessary to start Windows 7.
Safe Mode with Networking: This option loads the same processes as Safe Mode but also includes those that allow the networking functions in Windows 7 to work. You should choose this option if you think you might need to access the internet or your local network while troubleshooting in Safe Mode.
Safe Mode with Command Prompt: This version of Safe Mode also loads a minimum set of processes but starts the Command Prompt instead of Windows Explorer, the usual user interface. This is a valuable option if the Safe Mode option didn't work.
5.Wait for the Windows 7 files to load. The minimum system files necessary to run Windows 7 will now load. Each file being loaded will be displayed on the screen.
If Safe Mode freezes here, document the last Windows 7 file being loaded, then search the internet for troubleshooting advice.
6.To start Windows 7 in Safe Mode, you must log on with an account that has administrator permissions. If you're not sure if any of your personal accounts have administrator privileges, log in using your own account and see if that works.
7.Entry into Windows 7 Safe Mode should now be complete. Make any changes you need to make and then restart the computer. Assuming there are no remaining problems preventing it, the computer should boot to Windows 7 normally after a restart.