Used windows defender offline now windows won't start

Ok . And when you save the settings and it restarts what screen do you get ?

Have you tried Start Windows Normally ? You could also try to run Startup repair 3 times

Tutorial here below

Startup Repair - Run 3 Separate Times

empresssoul,

Please provide some additional information...

Is there a reason why WDO was run?
Was there a virus reported by your AntiVirus program?
If that is the case, do you recall the name of the virus?
If not the case, please explain further. Thanks!


Also, let's try the following...

You may want to print these instructions so you can have access to follow them.

Please plug a USB flash drive into a clean computer.
Go to Start > Computer
Double-click Computer, and select the flash drive.
Right-click and select: Format
Press Start on the Format prompt..

Next, use the Farbar Recovery Scan Tool Download
Select the 64-bit download.

Save the program to the >>> USB flash drive.
Remove the drive from the clean computer.

Next, plug the flash drive into the infected computer.

>>>Restart the computer.
As soon as the BIOS is loaded begin tapping the F8 key until the Advanced Boot Options menu appears.
Use the arrow keys to select the Repair your computer menu item.

Select your language settings, and click: Next
Select your User account and click: OK (If you did not set a password, leave blank.)

On the System Recovery Options menu you get the following options:
Startup Repair
System Restore
Windows Complete PC Restore
Windows Memory Diagnostic Tool
Scan your computer's memory for errors.
Command Prompt

Select: Command Prompt

In the Command window, at the blinking cursor type notepad and press: Enter
In Notepad, under the File menu select: Open
Double-click Computer, find the flash drive letter, remember what letter it is, click on it, and press: Open
Close out of Notepad.

Click the Command Prompt window
Type x:\frst64.exe, and press: Enter
Note: Replace the drive letter x with the drive letter of your flash drive!

The tool starts and prepares to run. Follow the prompts.
Click Yes to the disclaimer.
Press: Scan
When done, the program saves the FRST.txt report, on the flash drive.
Click the Command Prompt window, and type exit, and press: Enter

Back at the System Recovery Options, press: Shutdown

Remove the USB flash drive, plug it into the clean computer, and, please provide the FRST.txt in your reply.

A little addition tip from Cottonball's instructions . If you don't know your flash drive letter do the following

   Tip

Type the commands below to see what your letter is for the USB drive and press ENTER after each command

Diskpart
List volume

Ah this virus Trojan: Alureon ? That virus has a rootkit that messes with the MBR .