<IIsCompressionScheme Location ="/LM/W3SVC/Filters/Compression/gzip"
HcCompressionDll="%windir%\system32\inetsrv\gzip.dll"
HcCreateFlags="1"
HcDoDynamicCompression="TRUE"
HcDoOnDemandCompression="TRUE"
HcDoStaticCompression="TRUE"
HcDynamicCompressionLevel="9"
HcFileExtensions="htm
html
css
js
txt"
HcOnDemandCompLevel="10"
HcPriority="1"
HcScriptFileExtensions="asp
aspx
html
dll
exe
axd"
>
</IIsCompressionScheme>
加上axd就行