CMD appear and disappear when booting Win10 USB

[MEY]

It seems normal that a CMD appear and disappear when booting from a Win10 DVD made by Microsoft and sold on a DVD media.

But it doesn't seem normal that a CMD appears and disappears when booting from a Win10 USB or burned DVD created by downloaded files from Microsoft.

In the beginning there didn't appeared and disappeared any CMD when I booted from a Win10 USB. But after checking my outlook mail, it suddenly appeared. And I expect it to be caused by a rootkit or other type of malicious code. But I'm not totally sure.

I have tried to use PartedMagic NVME Secure Erase to delete all data on my SSD, but the CMD still appears when booting from USB.

If I go to the next page of the installation program and then abort the installation of Win10, the CMD doesn't appear the next time I boot from the USB. But if I then continue the installation or abort the installation, the CMD appears again the next time I boot from the USB.

I therefore expect the appearance to be caused by a rootkit or other kind of malicious code either on the SSD or on the motherboard. If it was on the USB or other place, I would expect it to appear every time the pc booted from the Win10 USB.

If I'm right in the cause of the appearance of the CMD, I really hope someone can help me get rid of it as I haven't got any luck with it in about half a year now.

[Corrine]

Hi, MEY.  Welcome to LandzDown Forum.

Please follow the Log Posting Instructions.

Thank you.

[winchester73]

https://www.bleepingcomputer.com/forums/t/711460/cmd-appear-and-disappear-when-booting-win-10-from-usb/

https://malwaretips.com/threads/cmd-appear-and-disappear-when-booting-windows-10-usb.97798/

It's going to be vital that you follow instructions given at only one help site, otherwise confusion will reign supreme.

[winchester73]

nasdaq has replied to you in the MalwareTips thread, and closed your BleepingComputer thread to avoid duplication ... I'd suggest you continue there since you haven't replied to Corrine here.

[plodr]

He also posted at MajorGeeks
https://forums.majorgeeks.com/threads/cmd-appear-and-disappear-when-booting-win10-usb.321300/

and who knows how many other places we haven't looked in.