My name is David.
Please power up the computer again and immediately start tapping the F8 key until a menu appears. Use the up and down arrow keys to highlight the "Last Known Good" option and then press the Enter key. Next, reboot the computer to determine whether or not the issue is resolved.
Please let me know if the issue is resolved after stepping through the above procedure or if you still need further assistance. Also, please provide positive feedback if you are satisfied with the service.
Ok good. So was it the "Last known good" procedure that you used to get the computer to boot?
Next perform a system restore which will roll back the computer configuration to the last working state. The following instructions are for Windows 7, so if your computer is running a different operating system please let me know:
Click the Windows Start button then Search and type System Restore in the Search box and then click the System Restore icon that appears in the search list. Click Next when the System Restore window appears and then click a restore point dated prior to when the issue first occurred and click Next. Confirm the System Restore and the restore will be applied and the computer will reboot. Then retest to see if the issue is resolved.Note that System Restore is reversible and does not impact your personal files.
Please let me know the result.