Error processing policy updates

Question

I've seen error event with Event ID 7997 in the Event log. Task category is Information Policy Management.

Error processing policy updates for site http://site for list listname.

Error: System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.Office.RecordsManagement.InformationPolicy.ListPolicySettings.get_UseListPolicy() at Microsoft.Office.RecordsManagement.InformationPolicy.Policy.<>c__DisplayClass5.<>c__DisplayClass7.b__1(SPList list) at Microsoft.Office.Server.Utilities.ContentIterator.ProcessLists(SPListCollection lists, ListProcessor listProcessor, ListProcessorErrorCallout errorCallout)

List listname is a part of custom feature.

Initial analysis points to Information management policy timer job.

What could be the cause of this error?

EDIT: Inner exception is Arithmetic overflow error converting expression to data type int. SQL Server stored procedure: proc_GetDocsMetaInfo

Answer 1

Turns out that in ListTemplate element, Type attribute value was set to a number greater than 10,000,000 in the Elements.xml for list definition. I reduced the value and error wasn't present any more.

For future reference, this must be obeyed:
BaseType + Type * 256 < 2^31 - 1

This means if BaseType == 0, Type must be less than 8,388,607.

Additional analysis: https://slavensemper.blogspot.com/2019/09/error-processing-policy-updates.html