Uploading Large Files (80mb+) with InstantForum or InstantKB



If you're attempting to upload files within either InstantForum or InstantKB and the upload times out or you receive a 404 page half way through the upload you may need to adjust some of the default thresholds provided within both InstantForum and InstantKB. These defaults can be adjusted via the InstantForum & InstantKB web.config files.

IIS 7 / 8+ (Integrated Application Pools)

For IIS 7 or above you'll need to add the entire <security/> element below to your <System.WebServer/> element…

<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="524288000"/>
</requestFiltering>
</security>
</system.webServer>

The maxAllowedContentLength attribute specifies the maximum length of content in a request, in bytes. The default value is 30000000.The value above 524288000 is equal to 500mb. Some examples are below...

  • 100 mb = 104857600 btyes
  • 200 mb = 209715200 btyes
  • 300 mb = 314572800 bytes

In addition you will also need to modify the maxRequestLength within the httpRuntime element to allow larger uploads. You can see below we've updated the maxRequestLength attribute to 307200 kilobytes or 300mb...

<httpRuntime maxRequestLength="307200" />​​

The maxRequestLength attribute within the httpRuntime element is measured in kilobytes. The example above 1536000 kilobytes or 1500 mb. You may wish to adjust this based on your requirements. Further possible examples are below...

  • 100 mb = 102400 kilobytes
  • 200 mb = 204800 kilobytes
  • 300 mb = 307200 kilobytes

IIS 6 / 7 (Classic .NET Application Pools)

With both InstantForum and InstantKB you'll need to modify the existing <httpRuntime/> element within the web.config as shown below…

<httpRuntime executionTimeout="6600" maxRequestLength="1536000"/>

The maxRequestLength attribute within the httpRuntime element is measured in kilobytes. The example above 1536000 kilobytes or 1500 mb. You may wish to adjust this based on your requirements. Further possible examples are below...

  • 100 mb = 102400 kilobytes
  • 200 mb = 204800 kilobytes
  • 300 mb = 307200 kilobytes

Other Tips​

If you still experience problems uploading large files please also modify the connection timeout property within IIS as shown below…

We hope this helps. If we can assist as always please don't hesitate to open a support request or contact us.