Computer Maintenance Tips

Minimize Crashes and Crash Damage:

1. Always shut the PC down properly. Windows creates temporary files that need to be closed before you turn off your machine. If you just throw the switch, these files are left in limbo. Not only might you lose program data that has not been saved, but it’s possible that badly written programs could be left in an unusable state.

2. When using Dial-Up Networking, do not physically disconnect your phone line from the PC before shutting down your connection. Windows can get hang waiting on the COM port.

3. Let Scandisk run during boot-up if your machine requires it.

4. Store data files on a different partition from the operating system. If Windows does crash and needs to be reinstalled, you won’t lose data.

5) Using Network: If you’re on a network, keep a copy of all your network settings (IP address, DNS, gateway, network card settings, and so on) handy.

What is bom sabado?

Bom Sabado means “Good Saturday” in Portuguese.

Social Networking sites are facing a major treat these days by hackers and viruses. Recently orkut a famous social networking site is attacked by a worm known as Bom Sabado. Orkut which is the Google owned website is the most used social networking site in Brazil and also has a significant number of users in India too.

Bom Sabado Worm is a java script based worm that spreads itself through orkut scraps.  Bon Sabado worm is the auto generated message which might look like another scrap from your buddy. This Scrap actually embeds a malicious JavaScript code which infects the profile of the person as soon as he opens the scrap page. Soon after this, the code is executed and it will make the user join bot communities automatically. The worm then starts posting similar scraps to the user friends using his name, thereby spreading itself.

Bom Sabado worm also steals browser cookies. Your browser will be hanged for some minutes or seconds

Orkut in its support site says that if you were affected by Bom Sabado make sure that you clear all your browser cookies and more importantly, change your Orkut password.

For Preventive measures from you can do the following:

     * Change your password.

    * Delete all of your cookies.

 

Antivirus

Antivirus or Anti-Virus is a computer programs that attempt to identify, neutralize or eliminate malicious software.  It can remove viruses from your computer.

Antivirus scanning software, or a virus scanner, is a program which examines all files in specified locations, the contents of memory, the operating system, the registry, unexpected program behavior, and anywhere else relevant with the intention of identifying and removing any malware.Antivirus software that protects computers from viruses and other malicious software. Earlier  Antivirus is used for designed exclusively to combat computer viruses however most modern antivirus software is now designed to combat a wide range of threats, including worms, phishing attacks, rootkits, Trojans, often described collectively as malware.

Antivirus software typically examines files when the computer’s operating system creates, opens, closes, or e-mails them. In this way it can detect a known virus immediately upon receipt. System administrators can schedule antivirus software will scan all files on the computer’s hard disk on a regular basis. Antivirus is protective software designed to defend your computer against malicious software. Malicious software or “malware” includes: viruses, Trojans, key loggers, hijackers, dialers, and other code that vandalizes or steals your computer contents. In order to be an effective defense, your antivirus software needs to run in the background at all times, and should be kept updated so it recognizes new versions of malicious software.

In computer technology, viruses are malicious software programs, a form of malware. By definition, viruses exist on local disk drives and spread from one computer to another through sharing of “infected” files. Common methods for spreading viruses include floppy disks, FTP file transfers, and copying files between shared network drives.

Once installed on a computer, a virus may modify or remove application and system files. Some viruses render a computer inoperable; others merely display startling screen messages to unsuspecting users.

Advanced antivirus software programs exist to combat viruses. By definition, antivirus software examines the contents of local hard drives to identify patterns of data called “signatures” that match known viruses. As new viruses are built, antivirus software manufacturers update their signature definitions to match and then deliver these definitions to users via network downloads

There are two different approaches used to identify malware, often in combination, although with an emphasis on the virus approach.

• examining (scanning) files, etc., for known viruses matching signatures in a virus       dictionary, and

• identifying suspicious behavior from any computer program which might indicate  infection. This approach is called heuristic analysis, and may include data captures, port monitoring and other methods.

When the antivirus software looks at a file, it refers to as viruses that antivirus software has identified. If a piece of code in the file matches any virus identified in the file, then the antivirus software can take one of the following actions:

1.   Attempt to repair the file by removing the virus itself from the file.

2.   Quarantine the file .

3.   Delete the infected file.

To achieve consistent success in the medium and long term, the virus approach requires frequent downloads of updated virus entries. Technically-inclined users, and those who want help find viruses not detected by the software, can send their infected files to the authors of antivirus software, who analyze them and include identifying features and removal information

Anti-virus approach can effectively contain virus outbreaks in the right circumstances, virus have tried to stay a step ahead of such software by writing “oligomorphic”, “polymorphic” and more recently “metamorphic” viruses

Emerging technique to deal with malware in general is white listing. Rather than looking for only known bad software, this technique prevents execution of all computer code except that which has been previously identified as trustworthy by the system administrator are unwanted by the system administrator are prevented from executing since they are not on the white list. .

138 Commands Used In DOS

1 ANSI.SYS — Defines functions that change display graphics, control cursor movement, and reassign keys.

2 APPEND — Causes MS-DOS to look in other directories when editing a file or running a command.

3 ARP — Displays, adds, and removes arp information from network devices

4 ASSIGN — Assign a drive letter to an alternate letter

5 ASSOC — View the file associations

6 AT — Schedule a time to execute commands or programs.

7 ATMADM — Lists connections and addresses seen by Windows ATM call manager.

8 ATTRIB — Display and change file attributes.

9 BATCH — NRecovery console command that executes a series of commands in a file.

10 BOOTCFG — Recovery console command that allows a user to view, modify, and rebuild the boot.ini

11 BREAK — Enable / disable CTRL + C feature.

12 CACLS — View and modify file ACL’s.

13 CALL — Calls a batch file from another batch file.

14 CD — Changes directories.

15 CHCP — Supplement the International keyboard and character set information.

16 CHDIR — Changes directories.

17 CHKDSK — Check the hard disk drive running FAT for errors.

18 CHKNTFS — Check the hard disk drive running NTFS for errors.

19 CHOICE — Specify a listing of multiple options within a batch file.

20 CLS — Clears the screen.

21 CMD — Opens the command interpreter.

22 COLOR — Easily change the foreground and background color of the
MS-DOS window.

23 COMP — Compares files.

24 COMPACT — Compresses and uncompress files.

25 CONTROL — Open control panel icons from the MS-DOS prompt.

26 CONVERT Convert FAT to NTFS.

27 COPY — Copy one or more files to an alternate location.

28 CTTY — Change the computers input/output devices.

29 DATE — View or change the systems date.

30 DEBUG — Debug utility to create assembly programs to modify hardware settings.

31 DEFRAG — Re-arrange the hard disk drive to help with loading programs.

32 DEL — Deletes one or more files.

33 DELETE — Recovery console command that deletes a file.

34 DELTREE — Deletes one or more files and/or directories.

35 DIR — List the contents of one or more directory.

36 DISABLE — Recovery console command that disables Windows system services or drivers.

37 DISKCOMP — Compare a disk with another disk.

38 DISKCOPY — Copy the contents of one disk and place them on another disk.

39 DOSKEY — Command to view and execute commands that have been run in the past.

40 DOSSHELL — A GUI to help with early MS-DOS users.

41 DRIVPARM — Enables overwrite of original device drivers.

42 ECHO — Displays messages and enables and disables echo.

43 EDIT — View and edit files.

44 EDLIN — View and edit files.

45 EMM386 — Load extended Memory Manager.

46 ENABLE — Recovery console command to enable a disable service or driver.

47 ENDLOCAL — Stops the localization of the environment changes
enabled by the setlocal command.

48 ERASE — Erase files from computer.

49 EXPAND — Expand a Microsoft Windows file back to it’s original format.

50 EXIT — Exit from the command interpreter.

51 EXTRACT — Extract files from the Microsoft Windows cabinets.

52 FASTHELP — Displays a listing of MS-DOS commands and information about them

53 FC — Compare files.

54 FDISK — Utility used to create partitions on the hard disk drive.

55 FIND — Search for text within a file.

56 FINDSTR — Searches for a string of text within a file.

57 FIXBOOT — Writes a new boot sector.

59 FIXMBR — Writes a new boot record to a disk drive.

60 FOR — Boolean used in batch files.

61 FORMAT — Command to erase and prepare a disk drive.

62 FTP — Command to connect and operate on a FTP server.

63 FTYPE — Displays or modifies file types used in file extension
associations.

64 GOTO — Moves a batch file to a specific label or location.

65 GRAFTABL — Show extended characters in graphics mode.

66 HELP — Display a listing of commands and brief explanation.

67 IF — Allows for batch files to perform conditional processing.

68 IFSHLP.SYS — 32-bit file manager.

69 IPCONFIG — Network command to view network adapter settings and assigned values.

70 KEYB — Change layout of keyboard.

71 LABEL — Change the label of a disk drive.

72 LH — Load a device driver in to high memory.

73 LISTSVC — Recovery console command that displays the services and drivers.

74 LOADFIX — Load a program above the first 64k.

75 LOADHIGH — Load a device driver in to high memory.

76 LOCK — Lock the hard disk drive.

77 LOGON — Recovery console command to list installations and enable administrator login.

78 MAP — Displays the device name of a drive.

79 MD — Command to create a new directory.

80 MEM — Display memory on system.

81 MKDIR — Command to create a new directory.

82 MODE — Modify the port or display settings.

83 MORE — Display one page at a time.

84 MOVE — Move one or more files from one directory to another DIRECTORY

85 MSAV — Early Microsoft Virus scanner.

86 MSD — Diagnostics utility.

87 MSCDEX — Utility used to load and provide access to the CD-ROM.

88 NBTSTAT — Displays protocol statistics and current TCP/IP connections using NBT

89 NET — Update, fix, or view the network or network settings

90 NETSH — Configure dynamic and static network information from MS-DOS.

91 NETSTAT — Display the TCP/IP network protocol statistics and information.

92 NLSFUNC — Load country specific information.

93 NSLOOKUP — Look up an IP address of a domain or host on a network.

94 PATH — View and modify the computers path location

95 PATHPING — View and locate locations of network latency

96 PAUSE — command used in batch files to stop the processing of a command.

97 PING — Test / send information to another network computer or network device .

98 POPD — Changes to the directory or network path stored by the pushd command.

99 POWER — Conserve power with computer portables.

100 PRINT — Prints data to a printer port.

101 PROMPT — View and change the MS-DOS prompt.

102 PUSHD — Stores a directory or network path in memory so it can be returned to at any time.

103 QBASIC — Open the QBasic.

104 RD — Removes an empty directory.

105 REN — Renames a file or directory.

106 RENAME — Renames a file or directory.

107 RMDIR — Removes an empty directory.

108 ROUTE — View and configure windows network route tables.

109 RUNAS — Enables a user to execute a program on another
computer.

110 SCANDISK — Run the scandisk utility.

111 SCANREG — Scan registry and recover registry from errors.

112 SET — Change one variable or string to another.

113 SETLOCAL — Enables local environments to be changed without affecting anything else.

114 SHARE — Installs support for file sharing and locking capabilities.

115 SETVER — Change MS-DOS version to trick older MS-DOS programs.

116 SHIFT — Changes the position of replaceable parameters in a batch program.

117 SHUTDOWN — Shutdown the computer from the MS-DOS prompt.

118 SMARTDRV — Create a disk cache in conventional memory or extended memory.

119 SORT — Sorts the input and displays the output to the screen.

120 START — Start a separate window in Windows from the MS-DOS prompt.

121 SUBST — Substitute a folder on your computer for another drive letter.

122 SWITCHES — Remove add functions from MS-DOS.

123 SYS — Transfer system files to disk drive.

124 TELNET — Telnet to another computer / device from the prompt.

125 TIME — View or modify the system time.

126 TITLE — Change the title of their MS-DOS window.

127 TRACERT — Visually view a network packets route across a network.

128 TREE — View a visual tree of the hard disk drive.

129 TYPE — Display the contents of a file.

130 UNDELETE — Undelete a file that has been deleted.

131 UNFORMAT — Unformat a hard disk drive.

132 UNLOCK — Unlock a disk drive.

133 VER — Display the version information.

134 VERIFY– Enables or disables the feature to determine if files have been written properly.

135 VOL — Displays the volume information about the designated drive.

136 XCOPY — Copy multiple files, directories, and/or drives from one location to another.

137 TRUENAME — When placed before a file, will display the whole directory in which it exists

138 TASKKILL — It allows you to kill those unneeded or locked up applications