Misleading Error Messages

Recently, a few of our customers ran into this error when hosting their WCF service with us on our IIS8 servers; Memory gates checking failed because the free memory is less than 5% of total memory.

Before you panic, this does not mean that our servers are overloaded or running out of memory as this check is performed on the total amount of memory available on the server.  5% in our hosting environment still means a lot of memory free.  Instead, you need to make sure ‘Full’ trust is enabled and that you add this to your web.config file:

<configuration>
<system.serviceModel>
<serviceHostingEnvironment ... minFreeMemoryPercentageToActivateService="0" />
</system.serviceModel>
</configuration>

The attribute to modify is minFreeMemoryPercentageToActivateService.  Setting it to 0 will bypass the check and allow the service to run.  For more information on the attribute, please see this link.