Symptom

You are running PRPC 6.3 SP1 in Internet Explorer 8 from any PRWebLDAP1 Servlet with the SSL/TLS protocol (HTTPS) on the Red Hat JBoss Enterprise Application Platform. Work object attachments do not open. The error Unable to download appears on your screen.

Attachments do open as expected in the PRServlet.

Error

Unable to download!pyNS_CPMPortal1_WorkTab0 from <server_ip_address>.

Unable to download from this site. The Requested Site is either unavailable or cannot be found. Please try again.

Explanation

This is known behavior for Internet Explorer 8 with SSL/TLS. The Cache-Control: no-cache header for secure requests prevents the caching of the secure resources on HTTPS. Proxy caching is disabled by default.

If you want work object attachments to allow caching of secure resources on Internet Explorer 8 with HTTPS, turn off the setting that disables proxy caching, but understand the consequences of doing so.

The following table compares how work object attachments in your Pega applications open in Internet Explorer 8 and Internet Explorer 9 over HTTP or HTTPS from PRServlet or PRWebLDAP.

Solution

Modify the context.xml file of the JBoss WAR file to change the default setting that disables proxy caching as described in JBoss Developer DisableCacheControl, repeated here for your convenience.

Tomcat adds a Cache-Control: no-cache header for secure requests to prevent caching of secure resources.

Starting with Red Hat JBoss Enterprise Application Platform 3.2.6 and later releases, the JBoss application server supports a WEB-INF/context.xml descriptor that allows you to customize the context of a WAR file.

1. Use the Context element to disable the Cache-Control header addition by specifying a myapp-web.war/WEB-INF/context.xml as shown here:
   <Context>
<Valve className="org.apache.catalina.authenticator.FormAuthenticator
"disableProxyCaching="false" ></Valve>
</Context>
2. After making this change, restart the server.

References

JBoss Developer DisableCacheControl

Internet Explorer is unable to open Office documents from an SSL Web site