Few days ago I had to deal with a virus that is very very hard to remove. So the best and easiest way to remove it is using an antivirus rescue CD. When you boot up the computer with a rescue cd which is usually a linux live CD, Windows is not loaded and the virus is inactive. This makes it 
easier for the antivirus to detect and clean the virus. I have encountered viruses that corrupts Windows so badly until you can’t even boot in to Safe Mode, you cannot install any antivirus because it auto terminates it and you can’t pin point where the virus is added to Windows auto startup location as it replaces one of your legitimate Windows system file.
Normally my first choice is to use Kaspersky Rescue CD but I had problems downloading it as I am getting very slow download speed. It managed to download until half way and then time out. Moreover it has been 2 months since Kaspersky Rescue CD last updated and I didn’t want to spend more time downloading the virus definition. I like Quick Heal Native Boot Scan as well but I didn’t want it to auto fix suspicious files that it finds. There is no way to configure it. Finally came Avira which is one of my favorite too. The Rescue CD ISO image file which is only 53MB in size and took only 7 minutes to download. The bootcd was last updated few days ago and I know I didn’t have to spend a lot of time updating the virus definition. When I boot up my Acer laptop with Avira AntiVir Rescue System, everything seems fine and was presented with a simple looking graphical user interface. When I click on any options such as “Remove infected files”, “Try to repair infected files” or “Rename Files, if they cannot be removed”, the whole system hung, and there is no respond at all. Sadly this is a bug that happens to most laptops such as Acer, Dell and HP. If you encounter such problem, here is how you can continue using Avira AntiVir Rescue System without relying on the GUI.
Just boot up the Avira AntiVir Rescue System as normal. Then press the number 1, hit enter and it should start loading vmlinuz and initrd.gz.
When the graphical user interface is fully loaded, simultaneously press Ctrl+Alt+Backspace.
That will bring you in to a black colored console screen that looks like DOS. Before you start typing anything, please be informed that the antivirus is programmed to type in German keyboard layout. For example, when you press the – key on your keyboard, you’ll notice that it chances to ß. Refer to the image below on what to type to get what character.
First we need to update the virus definition to the latest version. To do that, type the following command. There are TWO dashes.
antivir --update
To start a full scan, type the following command below. In Linux, everything is case sensitive. The Devices must have a capital D. What the command below does is scan everything on your hda1, tries to repair the infected files and rename the non-repairable files by adding a .xxx extension. You can also substitute the -ren command with -del to auto delete the non repairable files.
antivir -s -e -ren /media/Devices/hda1
When Avira AntiVir Rescue System has finished scanning, you should be able to boot in Windows. You can search in Windows for *.xxx files. These are the files that are non-repairable by Avira. You can get a list of command lines by typing antivir --help but you won’t be able to scroll up to see all the commands. So here are all the commands for your convenience.
Usage is: antivir [options] [path[\*.ext]] [*.ext]
where options are:
--help .......... display this help text (abbreviation: -h or -?)
--scan-mode=applies "extlist", "smart" or "all" scan methods:
extlist scans files according to their filename extension,
smart detects which files to scan from their name/content,
all scans all files regardless of their name or content
--allfiles ...... synonymous for --scan-mode=all
--version ....... show version information
--info .......... show list of recognized forms
--update ........ update antivir
--check ......... used with --update to check for updates
--temp=(dir) .... specify the directory for temporary files
--pid-dir=(dir) . specify the directory for PID files
--home-dir=(dir) location of executable, VDF and key files
-C (filename) ... name of configuration file
-s .............. scan subdirectories
--scan-in-archive files in archives will be extracted and scanned
-z .............. synonymous for --scan-in-archive (scan in archives, too)
--archive-max-size=N, --archive-max-recursion=N, --archive-max-ratio=N
anti DoS feature: do not scan archive content which would
exceed the given file size, nesting level or compression
factor limits on extraction (0 means unlimited)
--archive-max-count=N anti DoS feature: do not scan archive content which
has more than N files in a recursion level
--scan-in-mbox .. scan mailbox folders, too (might be time consuming!)
--heur-macro .... enable macro heuristics
--heur-nomacro .. disable macro heuristics
--heur-level=N .. setup heuristics level: 0=off, 1-3=low-high
-nolnk .......... do not follow symbolic links
-onefs .......... do not cross file systems while following links
-noboot ......... do not check any boot records
-nombr .......... do not check any master boot records
-nobreak ........ disable Ctl-C and Ctrl-Break
-nodef ......... do only check the given file types (eg. *.DOC)
-cf(filename) ... activate CRC check and name the database
-cv ............. calculate CRC over the whole file length (default 16k)
-cn ............. insert new files into the database
-cu ............. recalculate CRC values and update the database
-v .............. scan files completely (slower with possible false alerts)
-nopack ......... do not scan inside packed files
-e [-del | -ren] repair concerning files if possible
[-del] non-repairable files will be deleted
[-ren] non-repairable files will be renamed
-ren ............ rename concerning files (*.COM->*.XXX,...)
-del ............ delete concerning files
--moveto=(dir) .. quarantine concerning files
-dmdel .......... delete documents containing suspicious macros
-dmdas .......... delete all macros if one appears to be suspicious
-dmse ........... set exit code to 101 if any macro was found
-r1 ............. just log infections and warnings
-r2 ............. log all scanned paths in addition
-r3 ............. log all scanned files
-r4 ............. select verbose log mode
-rs ............. select single-line alert messages
-rf(filename) ... name of log file
%d = day, %m = month, %y = year (two digits each)
-ra ............. append new log data to existing file
-ro ............. overwrite existing log file
-q .............. quiet mode
-lang[:|=]DE .... use German texts
-lang[:|=]EN .... use English texts
-once ........... run only once a day
-if(dateiname) .. antivir uses the given ini file
--with-(type) ... detect other (non-virus but unwanted) software, too;
type may be e.g. "dial", "joke", "game", etc,
there is a --with-alltypes shortcut
--without-(type) like --with-(type), but disables this type
--alltypes ...... synonymous for --with-alltypes (obsolete)
--alert-urls=(yes|no) print URL for more detailed information on alerts
--warnings-as-alerts exit with a return code as if a concerning file
had been found when warnings have been issued
--exclude=(file) exclude files or directories from scan
--log-email=(addr) send out scan report by email, too
@(rspfile) ...... read parameters from the file (rspfile)
with each option in a separate linelist of return codes:
0: Normal program termination, nothing found, no error
1: Found concerning file or boot sector
2: An alert was found in memory
3: Suspicious file found
100: antivir only has displayed this help text
101: A macro was found in a document file
102: The option -once was given and antivir already ran today
200: Program aborted, not enough memory available
201: The given response file could not be found
202: Within a response file another @(rsp) directive was found
203: Invalid option
204: Invalid (non-existent) directory given at command line
205: The log file could not be created
210: antivir could not find a necessary dll file
211: Programm aborted, because the self check failed
212: The file antivir.vdf could not be read
213: An error occured during initialization
214: License key not found
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