Receiving "en_US.error.searchgln" error

I have never received this error before. Why am I getting this error and how can I fix it?

Symptoms

An "en_US.error.searchgln" error when click Search for a trade item in the Manage Items tab.

This error message "en_US.error.searchgln" can occur for any or all trade items while clicking Search.

To avoid this exception, change the following configuration settings:

From the Administration Console, confirm that the class path at <WAS> Application Servers > GDS_Application_server > Process Definition > Java Virtual Machine has this jar file added:<GDS_Install_Dir>/etc/ajax_jars/jsonrpc-cvs.jar
Make sure that you set the default language for supply side and demand side in the <GDS_Install_Dir>/etc/default/gds.properties file.
```
DEFAULT_LANGUAGE=en
```
Make sure the DefaultLocale property is set to "en_US" in the properties.xml file. The properties.xml file is in the appropriate data pool folder, which is in the demand or supply folder (based on the product installed), which is in the <GDS_Install_Dir>/etc/messaging/xml/ directory.
Restart the Global Data Synchronization for Product Master.