View source for New Executable

{{Short description|File format in early Windows and OS/2}}
{{Use dmy dates|date=May 2019|cs1-dates=y}}
{{Use list-defined references|date=September 2023}}
{{Infobox file format
| name                   = New Executable
| logo                   = 
| icon                   = 
| iconcaption            = 
| screenshot             = 
| caption                = 
| extension              = <code>[[.exe]]</code>, <code>.dll</code>, <code>.fon</code>, <code>.drv</code>
| mime                   = 
| type code              = 
| uniform type           = 
| conforms to            = 
| magic                  = 
| owner                  = 
| released               = <!-- {{Start date and age|YYYY|mm|dd|df=yes}} -->
| latest release version = 
| latest release date    = <!-- {{Start date and age|YYYY|mm|dd|df=yes}} -->
| genre                  = [[Executable]], [[dynamic-link library]]
| container for          = 
| contained by           = 
| extended from          = [[DOS MZ executable]]
| extended to            = [[Portable Executable]]
| standard               = 
| free                   = 
| url                    = 
}}

The '''New Executable''' ('''NE''' or '''NewEXE''') is a [[16-bit application|16-bit]] [[executable]] [[file format]], a successor to the [[DOS MZ executable]] format. It was used in [[Windows]] 1.0–3.x, [[Windows 9x]], [[MS-DOS 4.0 (multitasking)|multitasking MS-DOS 4.0]],<ref name="Brooks"/> [[OS/2]] 1.x, and the OS/2 subset of [[Windows NT#Major features|Windows NT]] up to version 5.0 (Windows 2000). An NE is also called a segmented executable.<ref name="Microsoft"/> It utilizes the [[286 protected mode]] or [[unreal mode]], and it can be 16-bit and 32-bit hybrid.<ref>https://wiki.osdev.org/NE</ref>

== History ==

The first product to be released using the New Executable format was [[Windows 1.0]] in 1985, followed by the 1986 [[MS-DOS 4.0 (multitasking)|multitasking MS-DOS 4.0]], which was a separate branch of MS-DOS development, released between mainstream MS-DOS versions 3.2 and 3.3, and sometimes referred to as "European MS-DOS 4.0".

The [[Portable Executable]] (PE) format replaced NE format in 32-bit and 64-bit versions of Windows, while [[Linear Executable]]s (LX) replaced NE for 32-bit programs in OS/2. [[VxD]] in [[Windows 9x]] also use [[Linear Executable|LE]] format.

== Compatibility ==
While designed for 16-bit [[Operating system|OS]]es, NE executables can be run on 32-bit [[Microsoft Windows|Windows]]. Beginning with Windows Vista, icon resources inside New Executables are not extracted and shown even by the 32-bit shell.<ref name="TechNet"/> 64-bit versions of Windows completely lack native support for running NE executables, because 64-bit Windows cannot run 16-bit programs on the processor without the help of an emulator.

Due to the rare and fairly complex nature of these files, only a few [[EXE packer|.EXE packers]] support it: WinLite, PackWin, [[PKLite 2.01]], and SLR Optloader or NeLite for OS/2. The NE format is also still used as (non-executable) container for <code>.fon</code> Microsoft Windows bitmapped fonts.

=== DOS stub ===
New (NE), linear (LX), and portable (PE) executables retain the DOS MZ format file header for [[backward compatibility]] with [[DOS]]. When run under DOS, a so-called ''DOS stub'' is executed which usually prints "This program cannot be run in DOS mode" and exits. This constitutes a minimal form of a so-called [[fat binary]]. Windows 1.0 executables, however, have their file header formatted in such a way that DOS refuses to run them with the "Program too big to fit in memory" error message; see [[Windows 1.0#Features|Windows 1.0 Features]].

==See also==
* [[COM file]]

==References==
{{Reflist|refs=
<ref name="Brooks">{{cite web |author-first=Vernon C. |author-last=Brooks |title=Information about the little known multitasking MS-DOS 4.0 |work=PC DOS Retro |url=https://pcdosretro.github.io/multitaskingmsdos4.htm |access-date=2014-02-13 |url-status=live |archive-url=https://web.archive.org/web/20200221141406/https://sites.google.com/site/pcdosretro/multitaskingdos4 |archive-date=2020-02-21}}</ref>
<ref name="Microsoft">{{cite web |id=https://support.microsoft.com/en-us/kb/65260 |title=Executable-File Header Format |publisher=[[Microsoft]] |url=http://benoit.papillault.free.fr/c/disc2/exefmt.txt |access-date=2014-02-13 |url-status=live |archive-url=https://web.archive.org/web/20230906155222/http://benoit.papillault.free.fr/c/disc2/exefmt.txt |archive-date=2023-09-06}}</ref>
<ref name="TechNet">[https://technet.microsoft.com/en-us/magazine/2008.05.windowsconfidential.aspx 16-Bit Icons Are So Passé: Windows Confidential - TechNet Magazine]</ref>
}}

{{Executables}}
{{OS/2}}

[[Category:Executable file formats]]
[[Category:Windows administration]]
[[Category:DOS technology]]
[[Category:OS/2 technology]]