Recently faced the big problem with big files. Not so big, just needed to post files with size about 10-20MB to aspx page. With usage of quite standard control on the page.
Everybody know ( if not - I notice here ) that in web.config you have HttpRuntime settings. And one of these settings is maxRequestLength .In theor, after adding of this line to web.config file everything should work fine.
<httpRuntime maxRequestLength="100000"/>
But in fact you can face the problem of limit in IIS. And this is a pain in the ass. Because you need to edit Metabase.xml on server. Sometimes this can be impossible, but sometimes you can do this yourself or ask support. Here is some insturctions to make big files uploads work for you.
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