When migrating a SharePoint site collection with enabled K2 Application to a new SharePoint environment by a third party migration tool, the activation step can fail with no details.
After enabling the SmartObject Server Logging, see KB000298, an unresolved group messages from BrokerpackageOut log similar to this one appears.
A site collection is copied from one SharePoint environment to another SharePoint environment with a third-party migration tool. During this copy, the K2 hidden list is also copied, and this K2 hidden list contains the SharePoint group ID of the source environment. The issue occurs when calling to get the SharePoint group name of a source environment that does not exist in the target SharePoint environment.
1. Obtain a valid SharePoint Group ID via the Management SmartObject (SharePoint 2013 > site_name > Management > Group > Get Groups method).
2. Navigate to hidden K2 Settings list URL: [SiteURL]/Lists/K2%20Settings/AllItems.aspx
For example, portal.denallix site is having issue with activation, https://portal.denallix.com/Lists/K2 Settings/AllItems.aspx
and update both Solution_Designer and Solution_Participants list items' values to a valid one from step 1.
3. Retry the App activation to resolve the issue.