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Support Article

FirstUseAssemblerException error in log



FirstUseAssemblerException errors appear in the logs on a sporadic basis.

Error Messages

ERROR  - Neither the primary page nor the provided pzInsKey was not found or in the database, cannot compile the rule!
Avoiding NPE by throwing a FirstUseAssemblerException() - [RULE-OBJ-ACTIVITY ORG-FW-WORK ACTIVITYNAME #20160625T213824.508 GMT user@:01-01-01 <no Circumstance> <no Circumstance Date> <no date range> available=Yes baserule=false{ udt: 20160625T214449.000 GMT { com.pegarules.generated.activity.ra_action_activityname_b1874716955a3dac255037036b4d49f7[Action] } }

Steps to Reproduce


Root Cause

A defect in Pegasystems’ code or rules.


The code in the stack trace has been refactored in a later release so the issue should no longer occur after updating to the latest Pega 7 release.

One option to address the issue in the meantime is to reassemble the candidates via the System Management Application (SMA).

  1. In SMA, navigate to the Advanced > Virtual Rule Table Cache Management page.
  2. Enter the Virtual Rule Key, which is <pxobjclass in CAPS> : <pxinsid in CAPS>. For example, the UpdateStatus activity would be RULE-OBJ-ACTIVITY : !UPDATESTATUS
  3. Click the Virtual Rule Table Cache Detail button.
  4. When the cache details are listed, click the Reassemble Candidates button.

Published July 27, 2016 - Updated October 8, 2020

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