How to set the maxAllowedContentLength to 500MB while running on IIS7?

The limit of requests in .Net can be configured from two properties together:

First

• Web.Config/system.web/httpRuntime/maxRequestLength
• Unit of measurement: kilobytes
• Default value 4096 KB (4 MB)
• Max. value 2147483647 KB (2 TB)

Second

• Web.Config/system.webServer/security/requestFiltering/requestLimits/maxAllowedContentLength (in bytes)
• Unit of measurement: bytes
• Default value 30000000 bytes (28.6 MB)
• Max. value 4294967295 bytes (4 GB)

References:

• http://www.whatsabyte.com/P1/byteconverter.htm
• https://www.iis.net/configreference/system.webserver/security/requestfiltering/requestlimits

Example:

<location path="upl">   <system.web>     <!--The default size is 4096 kilobytes (4 MB). MaxValue is 2147483647 KB (2 TB)-->     <!-- 100 MB in kilobytes -->     <httpRuntime maxRequestLength="102400" />   </system.web>   <system.webServer>     <security>       <requestFiltering>                   <!--The default size is 30000000 bytes (28.6 MB). MaxValue is 4294967295 bytes (4 GB)-->         <!-- 100 MB in bytes -->         <requestLimits maxAllowedContentLength="104857600" />       </requestFiltering>     </security>   </system.webServer> </location>

According to MSDN maxAllowedContentLength has type uint, its maximum value is 4,294,967,295 bytes = 3,99 gb

So it should work fine.

See also Request Limits article. Does IIS return one of these errors when the appropriate section is not configured at all?

See also: Maximum request length exceeded

IIS v10 (but this should be the same also for IIS 7.x)

Quick addition for people which are looking for respective max values

Max for maxAllowedContentLength is: UInt32.MaxValue 🡒 4294967295 bytes : ~4GB

Max for maxRequestLength is: Int32.MaxValue 🡒 2147483647 bytes : ~2GB

web.config

<?xml version="1.0" encoding="utf-8"?><configuration>  <system.web>    <!-- ~ 2GB -->    <httpRuntime maxRequestLength="2147483647" />  </system.web>  <system.webServer>    <security>      <requestFiltering>        <!-- ~ 4GB -->        <requestLimits maxAllowedContentLength="4294967295" />      </requestFiltering>    </security>  </system.webServer></configuration>