Hi Ian.

Have you tried to set the locations maxRequestLength? I think it is 4000 bytes by default.

<location path="Global">
 <httpRuntime maxRequestLength="1000000" />

Hope this helps!

- Tore Gjerdrum -

It doesn't work :-(

<location path="Global">
 <httpRuntime maxRequestLength="1000000" />

When uploading a file with the file manager the request is posted to the filemanager which is inside the UI folder, so you have to set the maxRequestLength for the UI folder instead of the Global folder.

If you're running on IIS7 there's also a request filtering module that has to be configured to allow for larger posts.

system.webServer/security/requestFiltering/requestLimits/@maxAllowedContentLength 

This directive is configured in bytes (not kB as is the case with maxRequestLength) 

I tested and it doesn't work :-(

you can use the advanced file upload.

or add the tag 

<requestLimits maxAllowedContentLength="your desired limit" />

So the final code will be 

<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="your desired limit" />
</requestFiltering>
</security>
</system.webServer>