To apply limit settings for all the applications on server we can use web.config.comments configuration file in C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\CONFIG
default for IIS server is 30 mb and we can reset this in web.config as mentioned below
<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="512000"/>
</requestFiltering>
</security>
</system.webServer>
we can reset this limit in web.config to enable larger file uploads
<system.web>
<httpRuntime executionTimeout="3600" maxRequestLength="512000"/>
</system.web>
this will allow files upto 500 mb to be uploaded.
<location path="DirectoryToUploadFiles">
<system.web>
<httpRuntime executionTimeout="3600" maxRequestLength="512000"/>
</system.web>
</location>