hi may i know what(or which ) are your favorite live cd antivirus to have always on usb stick and check for offline for virus? thanks
I don't use any. I always run malware cleanups from within Windows, as I find I can clean all malware that way. I have not needed to use a live CD/USB to clean malware for longer than I can remember.
I use Kaspersky Rescue Disk from here: https://support.kaspersky.com/viruses/rescuedisk If it would ever find anything I would restore clean image taken before infection. I prefer detect and restore to detect and clean procedure.
No live CD either, it is too much of a hassle to keep it updated, I prefer safe mode. My favorite portable scanners are CureIt, Emsisoft and KasperskyRemovalTool.
I don't need them, i format the partition, i don't trust cleaning apps. However i have plenty of diagnostic tools integrated in a suite i put on my USB.
If you are on win7 , you may try Hiren's Boot CD (containing lot of tools). I'm using something similar but because it is considered as "illegal" i won't mention its name here.
NeoSmart's Easy Recovery Essentials can somemes get a non booting computer working again, and includes an antivirus scanner. However, it's no free.
Norton / Symantec have the Norton Bootable Recovery Tool which I believe is now free to use. Introducing New Linux-based Norton Bootable Recovery Tool 2016.1.0
Hiren's BootCD Kaspersky Rescue Disk Avira Rescue CD Dr.Web Live CD BitDefender Rescue CD F-Secure Rescue CD
I don't use Live-AV-CDs anymore, for several reasons: To time consuming, not effective on fileless malware, sometimes not stable.. If I need to boot from USB-drive, I use MSDaRT, with integrated Offline-Defender. It's not free, nor do you have to pay for it, but it's part of the Microsoft Desktop Optimization Kit, that you only get with a suitable, paid Microsoft Account. Otherwise I recommend Kaspersky Rescue Disk, that includes an offline registry editor.