Updated: June 5, 2015
How to increase Max Allowed Content Length in IIS by adding security section to web.config.
I was trying to upload a big file that could be used by Conveyor, a package I've developed to export and import content for Umbraco, to the server. I was getting a blank screen, but by adding the below line to web.config and increasing it to 50MB I fixed the issue.
<system.webServer> ... <security> <requestFiltering> <!-- 50 MB --> <requestLimits maxAllowedContentLength="52428800" /> </requestFiltering> </security> ... </system.webServer>