upload and download over 30 MB file between silverlight and wcf service

Recently My project members and I are suffering from the problem that cannot upload and download over 30 MB file between silverlight and wcf service.

I googled lots of things and applied the suggestions but anything did not resolve our issue.

With this trouble remained I cannot sleep well so I'm writing this article now.

I searched more webs to find any hint to help us. Following sites can be helpful but the result will be known tomorrow.

http://ajaxuploader.com/large-file-upload-iis-debug.htm

This site suggests very good guide lines as below: 

1. Required

IIS7 - maxAllowedContentLength

IIS6 - maxRequestLength

2. Microsoft URL Scan

C:\WINDOWS\system32\inetsrv\urlscan\UrlScan.ini

MaxAllowedContentLength

3. File upload debug file

debug-upload.zip

http://ajaxuploader.com/large-file-upload-iis-asp-net.htm

This sites shows the required configuration for IIS7

1. Modify the maxAllowedContentLength setting in the web.config

<system.webServer>   <security>     <requestFiltering>       <requestLimits maxAllowedContentLength="2147483648" />     </requestFiltering>   </security> </system.webServer>

=> 2147483648 - 2 GB in size

2. Edit the request filtering feature settings and the request limits using IIS manager

• Open IIS Manager.
• Select the website that you want to configure.
• Make sure you are in Features View per the button at the bottom of the manager.
• Select Requests Filtering and open it by double-clicking the icon. The Request Filtering pane displays.
• From the Actions pane on the right hand side of the screen click Edit Feature Settings... link. The Edit Request Filtering Settings window displays.
• In the Request Limits section, enter the appropriate Maximum allowed content length (Bytes) and then click the OK button.
• Restart IIS.

3. Manually edit the ApplicationHost.config file

• Click Start. In the Start Search box, type Notepad. Right-click Notepad, and then click Run as administrator.
  
• On the File menu, click Open. In the File name box, type %windir%\system32\inetsrv\config\applicationhost.config, and then click Open.
• In the ApplicationHost.config file, locate the <requestLimits> node.

• Remove the maxAllowedContentLength property. Or, add a value that matches the size of the Content-Length header that the client sends as part of the request. By default, the value of the maxAllowedContentLength property is 30000000. 
  
  For example, modify the following configuration data inside the <requestFiltering> section.

  <requestLimits maxAllowedContentLength ="<length>" />

• Save the ApplicationHost.config file.

Finally to resolve this, we developed upload/download feature with new way: duplex communication on download and upload partitioning.

But this information is worth keeping in mind.