The WAS (Websphere Application Server) does not recognize the request for a resource though it exists in Web application (WAR file).
Solution: The WAS, by default, does not invoke the servlet filter for every resource until it is explicitly configured in server.
When a request comes for a URL resource, the WAS throws 404 error as if the requested resource is not available in application though it exists.
Follow the below steps to configure in WAS
a. Login to WAS Admin console application ( http(s)://MYHOST:9443/ibm/console ).
b. Expand 'Servers' node in left pane and click on 'Application Servers'.
c. Select the <'application server instance> from available application servers
d. Click on 'Web Container' under 'Container Settings' header.
e. Select 'custom properties' under 'Additional Properties' header.
f. Add or update the value to 'true' for property (com.ibm.ws.webcontainer.invokefilterscompatibility).
This helps WAS to invoke Filter compatibility for resources.
g. Save and restart the app server instance.
Please see below image for reference.