Windows 10: Can windows defender offline search for rootkits be installed and queued from a thumb drive?

I had an attachment that came supposedly from a .tx.gov domain that when I opened it I found as opening a webpage with a ****.ru domain. So assuming the worst I scanned with three different commercial software packages Eset, Trendmicro, Malwarebytes which found nothing. Tried Microsoft safety security scanner as well as their Malicious Software Removal Tool and neither one of them would finish over 60 hrs and 10 hrs respectively despite continuing to see the file names change. Looking further the security updates are not installing for Defender 0x80070643 and the Windows Security st

:)

 

Windows Defender for Win10 v1709 and Rootkits?

Windows Defender can detect rootkits, then tell you to run Defender Offline to remove them.

https://support.microsoft.com/en-gb/...-protect-my-pc

 

Windows Defender Offline

Having read the response from Cyber_Defend_Team, my opinion is that the suggestion is a reach solution. An update would only be applicable if it included a fix for a reported issue of unable to invoke a Defender Offline scan or code that was previously preventing
the feature from being executed.

In addition Windows 10 installs released updates automatically with the only requirement to initiate a restart at a convenient time by the user.

The work around I have used since was to download Defender Offline as a bootable cd and execute it to receive confirmation that no know rootkits have been installed. The outcome was reassuring and excluding zero day rootkits and other malware, Defender is
effective in protecting W10.

Unfortunately activation of the Scan Offline button still does not initiate a restart.

 

am I infected with a rootkit

I was refering to Windows defender offline,it has been suggested that if you think you have a root kit then using Windows Defender offline is a good tool.

my concern is whether Windows Defender offline is good enough and whether it would affect the operating system if it deletes a rootkit.