If a Network Discovery task is scheduled, then the page gives an error "Server Error in '/Altiris/DiscoveryTasks' Application".
The error appears across different pages on Symantec Management Console, like:
Home> Discovery and Inventory> Network Discovery
Home> First Time Setup> Network Discovery, and
Settings> Console> Web Parts> Network Discovery Task Management
Symantec Management Platform 8.0 Hot Fix version 4.
Server Error in '/Altiris/DiscoveryTasks' Application
Error seen in the Symantec Management Platform (SMP) Log Viewer and on the page:
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.ConstraintException: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.