Cannot download assetbundle in ios. (Invalid Unity Web File)

Hello, I'm using assetbundle in both android and ios developement.

My program works well in android but has a problem in ios.

I built assetbundle normally, and uploaded them to a IIS web server using ftp, mput command.
But while I try to download them with WWW(url) method a error occurs.(www.error)
It says "Invalid Unity Web File(Decompression Failure)".
One thing is that when I try to download it from local storage(with WWW("file://...")) assetbundle is normally downloaded and no error occurs.
There is no other problem in web server, because other types of files(not assetbundle, some xml or binary files) are downloaded normally with WWW() method.

Do I missing something? Please, any help is appreciated.

 

I am self-answering. When I was using ftp the transfer mode was ascii, so file size has changed, and assetbundle file has corrupt and could not be read from unity. I changed transfer mode to binary and it has been solved.

 

to Zeratul from "Aure"
greate dude . you solved my big problem . tanx a lot.
"captain jimy raynor"

 

Zeratul is my Hero!

 

Zeratul thanks a lot!!!

 

how i can change transfer mode to binary?

 

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