If you can't access the desktop, let your computer fail to start at least three times to trigger the automatic repair environment, and then do the following:
1. Select Troubleshoot on the Choose an option screen.
2. Click on Advanced options.
3. Click on Start Settings.
4. Click the Restart button.
5. After your computer reboots, press F4 or the 4 key to select Enable Safe Mode.
Once you're in safe mode, depending on what's causing the problem, you can use the following steps to uninstall an update or device driver.