dSeries Web Client shows blank page on browser

Products

• ESP dSeries Workload Automation - System Agent (dSeries)
• ESP dSeries Workload Automation - Scheduler (dSeries)
• ESP dSeries Workload Automation - Business Agents (dSeries)
• ESP dSeries Workload Automation

Issue/Introduction

When accessing the webpage of DE WebUI / Web Client, nothing appears in the browser.  In cases, users may see some certificate error.

The apache logs will show errors like these:

2025-10-01T20:04:57.033327Z https-jsse-nio-8443-exec-1 ERROR This is a error log2025-10-01T20:04:57.037939Z https-jsse-nio-8443-exec-1 FATAL This is a fatal log2025-10-01T20:05:01.720252Z https-jsse-nio-8443-exec-4 ERROR Forwarding to error page from request [/] due to exception [Cannot invoke "String.substring(int)" because "authorization" is null]
java.lang.NullPointerException: Cannot invoke "String.substring(int)" because "authorization" is null
 at com.ca.de.ui.filters.DeUiWebInterceptor.preHandle(DeUiWebInterceptor.java:121)
 at org.springframework.web.servlet.HandlerExecutionChain.applyPreHandle(HandlerExecutionChain.java:146)
 at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1084)
 at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:979)
 at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014)
 at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903)
 at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:564)

....

Environment

Workload Automation DE: 12.3 or above

Workload Automation DE Web Client: 12.3 or above

Cause

The SSL certificate may not be valid or is for incorrect hosts.

Resolution

If the hostname changed, then the SSL certificate will not be valid.  Make sure to regenerate the certificate and add it to the keystore.  The default location of keystore is:

 <DE_WebUI_dir>/apache-tomcat/conf/.keystore 

If self signed SSL certificate was used, then regenerate the certificate, see this KD for more details.  For CA (external) signed, consult your Network / System admin on creating and signing of certificates.

Once the certificate has been created, delete old certificate under alias 'wade'.  This the default alias used when installing DE Web Client.

Import the certificate using the same alias, wade.  If the same alias is not used, then make sure to update the alias in server.xml in

<DE_WebUI_dir>/apache-tomcat/conf/server.xml