经常我在用IIS做为下载服务器的时候有时传上去的文件比如 xxx.iso 文件名名是传上去了，但是用http打开的时候确显示为 404 文件不存在。

这其实是IIS对文件的一种保护，不在IIS指定的MIME类型里的文件显不会操作。

觉见的有 mp4 / flv / iso / 7z / apk 等扩展名的文件 iis 本身是没c指定MIME类型的，这类文件默认在IIS里是不能下载的。

我们可以打开IIS 在 xx本地服务器上 右键 -> 属性 然后在 MIME类型 中查看已经的MIME格式

比如我们需要IIS支持 MP4 文件下载可以这么设置：(这里我们对IIS全局进行设置、如果只针对某一个站点可以直接设置站点的)

1、在 网站 上t键 选属性

2、在打开的 网站 属性 上选择 HTTP 头 再点 MIME类型按钮

3、在打开的窗本中 点下 新建

4、在弹出的 MIME类型框上 扩展名 MP4 MIME类型为： application/octet-stream

这样IIS就可以支持 MP4下载了。

下面列出一些常用的 扩展名的 MIME类型。

如果不知道MIME类型 可以写通用的: application/octet-stream

还有一些规律如果是文本类的让IE可以直接打开的 MIME 可以为 text/扩展名

如果是音频打开的时候让windows自动播放的可以用 audio/扩展名

扩展名类型/子类型

application/octet-stream

323

text/h323

acx

application/internet-property-stream

ai

application/postscript

aif

audio/x-aiff

aifc

audio/x-aiff

aiff

audio/x-aiff

asf

video/x-ms-asf

asr

video/x-ms-asf

asx

video/x-ms-asf

au

audio/basic

avi

video/x-msvideo

axs

application/olescript

bas

text/plain

bcpio

application/x-bcpio

bin

application/octet-stream

bmp

image/bmp

c

text/plain

cat

application/vnd.ms-pkiseccat

cdf

application/x-cdf

cer

application/x-x509-ca-cert

class

application/octet-stream

clp

application/x-msclip

cmx

image/x-cmx

cod

image/cis-cod

cpio

application/x-cpio

crd

application/x-mscardfile

crl

application/pkix-crl

crt

application/x-x509-ca-cert

csh

application/x-csh

css

text/css

dcr

application/x-director

der

application/x-x509-ca-cert

dir

application/x-director

dll

application/x-msdownload

dms

application/octet-stream

doc

application/msword

dot

application/msword

dvi

application/x-dvi

dxr

application/x-director

eps

application/postscript

etx

text/x-setext

evy

application/envoy

exe

application/octet-stream

fif

application/fractals

flr

x-world/x-vrml

gif

image/gif

gtar

application/x-gtar

gz

application/x-gzip

h

text/plain

hdf

application/x-hdf

hlp

application/winhlp

hqx

application/mac-binhex40

hta

application/hta

htc

text/x-component

htm

text/html

html

text/html

htt

text/webviewhtml

ico

image/x-icon

ief

image/ief

iii

application/x-iphone

ins

application/x-internet-signup

isp

application/x-internet-signup

jfif

image/pipeg

jpe

image/jpeg

jpeg

image/jpeg

jpg

image/jpeg

js

application/x-javascript

latex

application/x-latex

lha

application/octet-stream

lsf

video/x-la-asf

lsx

video/x-la-asf

lzh

application/octet-stream

m13

application/x-msmediaview

m14

application/x-msmediaview

m3u

audio/x-mpegurl

man

application/x-troff-man

mdb

application/x-msaccess

me

application/x-troff-me

mht

message/rfc822

mhtml

message/rfc822

mid

audio/mid

mny

application/x-msmoney

mov

movie

video/x-sgi-movie

mp2

video/mpeg

mp3

audio/mpeg

mpa

video/mpeg

mpe

video/mpeg

mpeg

video/mpeg

mpg

video/mpeg

mpp

application/vnd.ms-project

mpv2

video/mpeg

ms

application/x-troff-ms

mvb

application/x-msmediaview

nws

message/rfc822

oda

application/oda

p10

application/pkcs10

p12

application/x-pkcs12

p7b

application/x-pkcs7-certificates

p7c

application/x-pkcs7-mime

p7m

application/x-pkcs7-mime

p7r

application/x-pkcs7-certreqresp

p7s

application/x-pkcs7-signature

pbm

image/x-portable-bitmap

pdf

application/pdf

pfx

application/x-pkcs12

pgm

image/x-portable-graymap

pko

application/ynd.ms-pkipko

pma

application/x-perfmon

pmc

application/x-perfmon

pml

application/x-perfmon

pmr

application/x-perfmon

pmw

application/x-perfmon

pnm

image/x-portable-anymap

pot,

application/vnd.ms-powerpoint

ppm

image/x-portable-pixmap

application/vnd.ms-powerpoint

ppt

application/vnd.ms-powerpoint

prf

application/pics-rules

ps

application/postscript

pub

application/x-mspublisher

qt

video/quicktime

ra

audio/x-pn-realaudio

ram

audio/x-pn-realaudio

ras

image/x-cmu-raster

rgb

image/x-rgb

rmi

audio/mid

roff

application/x-troff

rtf

application/rtf

rtx

text/richtext

scd

application/x-msschedule

sct

text/scriptlet

setpay

application/set-payment-initiation

setreg

application/set-registration-initiation

sh

application/x-sh

shar

application/x-shar

sit

application/x-stuffit

snd

audio/basic

spc

application/x-pkcs7-certificates

spl

application/futuresplash

src

application/x-wais-source

sst

application/vnd.ms-pkicertstore

stl

application/vnd.ms-pkistl

stm

text/html

svg

image/svg+xml

sv4cpio

application/x-sv4cpio

sv4crc

application/x-sv4crc

swf

application/x-shockwave-flash

t

application/x-troff

tar

application/x-tar

tcl

application/x-tcl

tex

application/x-tex

texi

application/x-texinfo

texinfo

application/x-texinfo

tgz

application/x-compressed

tif

image/tiff

tiff

image/tiff

tr

application/x-troff

trm

application/x-msterminal

tsv

text/tab-separated-values

txt

text/plain

再添几个常用的

apk    application/vnd.android.package-archive

MRP文件(国内普遍的手机)

.mrp application/octet-stream

IPA文件(IPHONE)

.ipa application/iphone-package-archive

.deb application/x-debian-package-archive

APK文件(安卓系统)

.apk application/vnd.android.package-archive

CAB文件(Windows Mobile)

.cab application/vnd.cab-com-archive

XAP文件(Windows Phone 7)

.xap application/x-silverlight-app

SIS文件(symbian平台/S60V1)

.sis application/vnd.symbian.install-archive *(下有)

SISX文件(symbian平台/S60V3/V5)

.sisx application/vnd.symbian.epoc/x-sisx-app