Skip to main content

This content has been archived and is no longer being updated. Links may not function; however, this content may be relevant to outdated versions of the product.

Support Article

Blank screen after system is idle for sometime



System is showing up a blank screen, after the system is left idle for sometime. The http request and http response is going in a loop, as revealed using fiddler. From SMA, user found that the requestor session is not passivated.

Error Messages

No error messages displayed, blank white screen.

Steps to Reproduce

This is reproducible with PRPC 7.1.8 using PRExternal authentication Only.

Start fiddler
Log into PRPC using end user portal.
In SMA stop requestor.
In the end user portal click anywhere on the screen.
You will see a white screen and fiddler you will see the same request repeating.

Root Cause

This problem is reproducible only when using PRExternal style authentication and there is some sort of load balancing issue in place. PRExternal has been depreciated in since PRPC 5.4 and should not be used in PRPC 7.1.X. 

When a PRPC system receives a Pega-RULES cookie that it can't match to a requestor, passivated or other, the engine level calls the activity pzHandleUnknownSession. This returns HTML, pzUnknowSessionAlert, that tries to redirect to the user to the login page but with PRExternal style authentication this keeps looping and looping, the request keeps returning the same HTML.


Same as SA-16874.

PRExternal style authentication is depreciated. Upgrade to PRCustom and then a load balancing issue occurs the user will properly be directed to a PRPC login screen.

Note: This does not resolve the load balancing issue that must be happening to get this problem when using PRExternal authentication. 


Published January 31, 2016 - Updated October 8, 2020

Was this useful?

0% found this useful

Have a question? Get answers now.

Visit the Collaboration Center to ask questions, engage in discussions, share ideas, and help others.

Did you find this content helpful?

Want to help us improve this content?

We'd prefer it if you saw us at our best.

Pega Community has detected you are using a browser which may prevent you from experiencing the site as intended. To improve your experience, please update your browser.

Close Deprecation Notice
Contact us