Diagnosis
The document to be reversed (document &V1&) belongs to an installationgroup. It is a primary installation document.
In this case, the complete installation group, that is all documentsconnected to document &V1& as well as document &V1& itself, must bereversed together.
An internal error has occurred during the reversal of document &V1&.
As a result, the installation group cannot be reversed.

Procedure
Correct the error in document &V1& and start the reversal again.