Windows Defender Offline scan useless?

[diamante]

Would any fellow members of this community who are running up-to-date versions of Windows 10 please try running a Windows Defender offline scan and let me know if it completes successfully, with the scan results subsequently displayed as the last scan results in Windows security settings? Yesterday, after getting a strange error message from Windows Defender on one laptop,  I tried running offline scans on three different HP laptops. In all three cases, the laptop rebooted without warning while the scan was in progress. After rebooting, there was no indication that an offline scan had occurred. In Windows security settings, the last scan reported was the previous quick or full scan. This behavior is disconcerting on multiple levels...

[Jeet_singh]

@diamante,

Thank you for posting your query on HP Community<

D you have any third party anti virus program installed on your PC.

The issue could be due to some third party software conflict. At first, I would suggest you to boot the computer into clean boot and then try to install the updates.

Method 1: To help troubleshoot error messages and other issues, you can start Windows by using a minimal set of drivers and startup programs. This kind of startup is known as a "clean boot." A clean boot helps eliminate software conflicts.

Try performing a clean boot on your PC and check if it helps.

From Start, search for msconfig.
Select System Configuration from the search results.
On the Services tab of the System Configuration dialog box, tap or click to select the Hide all Microsoft services check box, and then tap or click Disable all.
On the Startup tab of the System Configuration dialog box, tap or click Open Task Manager.
On the Startup tab in Task Manager, for each startup item, select the item and then click Disable.
Close Task Manager.
On the Startup tab of the System Configuration dialog box, tap or click OK, and then restart the computer.

Method 2: I would suggest you to run System File Checker tool and check.

System File Checker is a utility in Windows that allows users to scan for corruptions in Windows system files and restore corrupted files.

Press Windows key + X and click Command Prompt (Admin)

Type the following command and press Enter

sfc /scannow

Note: Do not close this Command Prompt window until the verification is 100% complete. The scan results will be shown after this process is finished.

Method 3: I would suggest you to re-register Windows Defender DLL files by running the following commands in Command Prompt and check.

a. Press Windows key + X and click Command Prompt (Admin)

b. Type the following commands one by one and press Enter

regsvr32 wuaueng.dll
regsvr32 wucltui.dll
regsvr32 softpub.dll
regsvr32 wintrust.dll
regsvr32 initpki.dll
regsvr32 wups.dll
regsvr32 wuweb.dll
regsvr32 atl.dll
regsvr32 mssip32.dll

c. Restart the computer and check the status.

Let me know how it goes for further assistance!

That said, If the information I've provided was helpful, give us some reinforcement by clicking the Accepted Solution and Kudos buttons, that'll help us and others see that we've got the answers!

Have a great day!

[diamante]

Thank you for the reply, Jeet_singh. I will try your suggestions as soon as possible. I do not have any third-party antivirus products on any of these computers. As for your Method 1, I'm not sure if that's relevant, because the offline scan causes the computer to reboot and run the scan before Windows loads.

No one has replied to this message confirming that the Windows Defender offline scan is indeed working as it should. Would anyone be willing to run a scan as a test? It takes about 15 minutes. Start menu, Settings, Update & Security, Windows Security, Virus & Threat Protection, Scan Options, Windows Defender Offline Scan. After the scan completes and your computer restarts, you can confirm that it completed successfully if you return to the Virus & Threat Protection screen and it says that the last scan was the offline scan that you just performed. On the three HP laptops I have tested, full scans are successful but offline scans (which are supposed to be able to detect and eliminate viruses that can hide while Windows is running) will not complete. Thank you to anyone who is willing to test this.

What I have done so far is the following: I performed a System Restore taking the system back to before the last major Windows 10 update that had been installed within the past two weeks or so. I also downloaded the Trend Micro Rescue Disk tool and burned a bootable disk with their latest antivirus definitions. (Trend Micro is an antivirus company based in Tokyo that I believe to be trustworthy.) I also tried using a Bitdefender Rescue disk, but that seemed to be trying to get too fancy--it booted my computer in a Linux environment and tried to connect to the Internet itself to download its latest definitions before scanning. It seemed to be unable to install the necessary drivers for my networking hardware. In any case, I did a complete scan with the Trend Micro Rescue Disk (after doing the System Restore) and it detected no threats. Also, I have not received any more threat notifications from Windows Defender.

The error message that I originally received said that I had a Trojan virus called Win32-Occamy.C. Supposedly the infected file was D:\Eautorun.exe, but my computer doesn't even have a D drive. I just confirmed that no D drive shows up in Disk Management under Computer Management. When I looked at the details in Windows Defender, it said that the alert level was serious and that the status was "Error." The scan summary notifications that I received from Windows Defender said something to the effect that the threats had been dealt with, but after a short time they disappeared from the Windows Defender history, so it was all very weird.

[Jeet_singh]

Thank you for replying, @diamante,

Just wanted to check if you have received any threats from Microsoft Defender. If you haven't received any more threats from MS defender, it would be safe to assume the threats has been dealt with. 

You may also refer to this support document - Windows Defender Antivirus in Windows 10

I hope this information helps. Let me know if you need any further assistance. 

Take care and have a great day!

Thank you 🙂

[diamante]

Thank you. I have not had any further problems, or warnings from Windows Defender. However, I do still wonder why the Windows Defender offline scan does not run correctly on any of my three computers. I guess this will remain a mystery. Maybe it's a Microsoft bug...

[Jeet_singh]

@diamante,

I'm glad to hear that it seems to be working. However, you seem to have a concern regarding the Windows defender. 

Do visit our HP Forums and drop us a message anytime you need help.

To simply say thanks for my efforts to assist you, please click the "Thumbs Up" button to give me a Kudos.
And mark my public post as Accepted Solution to help others find a similar solution as you have.

Take care now and do have a fabulous week ahead. 🙂
Regards,

[iceman2]

Just ran one tonight turned my back while PC was booting so don't know if scan started but when I checked the screen it was stuck on a keyboard language setup screen with US english selected but screen was frozen. Had to hit power button to restart. 

Not surprised if this feature doesn't work because defender keeps flagging microsoft files as ones being blocked by Controlled Folder Access. Any antivirus that cant recognize legitimate files on the HD can't be worth much. Thinking of paying for a malwarebytes subscription.