Increase the length of time It take a page to time out
To set the execution timeout, edit the Web.config settings:

1. Browse to the NetCommunity web.config file in Windows Explorer on the Web server
2. Right-click on the file and remove the Read-only property
3. Open web.config using Notepad
4. Search for <httpRuntime maxRequestLength="12288" />
5. Change the following line:

<httpRuntime useFullyQualifiedRedirectUrl="true" requestValidationMode="2.0" maxRequestLength="10240" />
 
To match the line below:
 
<httpRuntime executionTimeout="600" useFullyQualifiedRedirectUrl="true" requestValidationMode="2.0" maxRequestLength="10240" />


7. Once this change has been made, save and close the Web.Config file and Restart the IIS Admin Service.

This will change the execution timeout to 10 minutes and can be increased if required. Note that a backup of your web.config file should be taken prior to making any changes.