Information, tips and instructions

File Extension SYS

SYS is mostly used for system files for Microsoft operating systems. These files contain driver information and several computer configurations. They can be opened on platforms PC and Mac. Sys files are only accessible on Mac platforms with Windows components installed.

Most sys files are hidden and protected by the operating system. Editing these files is highly discouraged. Some third party applications create their own sys files for proper configuration. Windows XP's sfc /scanonce, accessed through the command prompt, is part of the Windows File Protection (WFP) essential for replacing damaged systems files.

CONFIG.SYS contains essential instructions set for a computer to function including DOS configuration while MSDOS.SYS contains the real DOS information. In most systems, sys file can be accessed through C:\Windows\system32 address.

Sys files are some times the perfect prey for most viruses and worms spreading over the Internet. Some worm duplicate system files including CONFIG.sys and others create their own system to infect a computer and prevent being detected by anti-virus software.

The sigverif application is Windows help maintain a system's integrity by scanning digitally signed and unsigned system files created by Windows and other third party applications that need to install there own system files. Applications such as Notepad and Wordpad can open files with sys extension however ASCII codes will appear instead of a human readable text.

Similar file extensions

• File Extension EXE - Windows Executable
• File Extension DLL - Dynamic Link Library
• File Extension INI - Application Initialization Parameters