Enable files up to 10MB to be posted, changes the buffering threshold to 100KB : httpRuntime « Configuration « ASP.NET Tutorial

1. ASP.NET Tutorial
2. Configuration
3. httpRuntime

<configuration>
<system.web>
  <httpRuntime
       maxRequestLength="10240"
       requestLengthDiskThreshold="100" />
</system.web>
</configuration>