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Support Article

Instance goes down due to NullPointerExceptions



Unable to log in with the following error message displayed on screen and log file.
Status fail
Message Problem invoking function: pega_rules_string.whatComesAfterLast--(String,char), com.pegarules.generated.whatComesAfterLast_060301_AQFt9UNTyufX701z4waYCg
Operator ID your_operator
Requestor ID H7215922F8887EF0D6470A498075102B1
Timestamp Mon Oct 27 18:51:10 GMT+00:00 2014
Engine Version PegaRULES 6.3 SP1 (coreAssemblyCached_63SP1_38)

However, after a subsequent server restart users are able to log in. 

Error Messages

2014-10-27 18:51:10,806 [ http-8443-2] [ STANDARD] [ your_accessgroup:01.04.01] (l.library.LibraryMetadataCache) ERROR Your_host| your_operator - Problem invoking function: pega_rules_string.whatComesAfterLast--(String,char)
java.lang.ClassNotFoundException: com.pegarules.generated.whatComesAfterLast_060301_AQFt9UNTyufX701z4waYCg
at com.pega.pegarules.bootstrap.loader.PRAppLoader.loadClass(
at com.pega.pegarults.bootstrap.loader.PRAppLoader.loadClass(
at com.pega.pegarules.exec.internal.util.classloader.PRClassLoaderDB.loadClass(
at java.lang.ClassLoader.loadClass(

Steps to Reproduce

There is no specific use case to replicate this behavior.

Root Cause

In the Rule-Utility-Libraries, the cached lists and rules were inconsistent or stale. The server startup logs indicate that in the Rule-Utility-Libraries, the cached lists and rules were not recompiled. The libraries and cached rules will be re-assembled only if the “PegaRULES extract marker” file has been successfully deleted. However, in this case it was evidently not. 


Delete the ExtractMarker.txt file from the PegaTemp directory and restart the server.
Suggest Edit

Published January 31, 2016 - Updated October 8, 2020

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