Unable to assign resources to an existing service item already representing an existing resource in IT shop (4329161)

In earlier versions of One Identity Manager prior to v8.1.2, it is possible to group multiple requestable items (e.g. QERResources, ADSGroups, ESets, etc) to an existing service item (AccProduct) in IT shop.

After upgrading to One Identity Manager v8.1.2 or later, when adding requestable resources to an existing service item which already has requestable resources assigned will yield the following error message:

'This product cannot be used because it is already assigned to the following object(s): <Resource>'

By design, there should always be a 1:1 relation between service items and requestables, but OneIM versions prior to 8.1.2 did not enforce this intention and tolerated grouping several requestables to a single service item. However, this data situation caused other issues such as NullReference exceptions, page grids with wrong values or refusal of ITShop requests, and is a concern for the upcoming Application Onboarding module.

Starting with version 8.1.2 and feature #32459, OneIM enforces the design via customizer. The cause for the above error message is the result of this customizer check.

The behavior is intended. While OneIM continues to allow pre-existing service items with several requestables from before an upgrade to 8.1.2 or later, a QBMConsistencyCheck "Duplicate use of AccProduct is available to identify duplicate uses of service item and the recommendation is to resolve this data situation.

An automatic repair method is not possible and not part of the consistency check.

In case several requestables should be available through a single service item, the suggestion is to use ESets to group the requestables and make the ESets available through the ITShop instead.