This post is about an issue that comes with Apex-managed sharing, i.e.

System.SObjectException: Field is not writeable: Sobject__Share.RowCause

We faced this problem recently and tried searching for this problem on force.com boards, but no solution was available, I just found few open questions like

• http://boards.developerforce.com/t5/Apex-Code-Development/Urgent-help-migration-error-quot-RowCause-filed-not-writable/td-p/137271

• http://boards.developerforce.com/t5/Apex-Code-Development/Can-Apex-Managed-Sharing-be-used-in-a-Class-declared-with-quot/td-p/164916

Read More: https://abhinav.fyi/resolved-field-is-not-writeable-sobject__share-rowcause/