Is there any API available to Restore Archived RQM resource?
One answer
These are the currently documented APIs:
https://jazz.net/wiki/bin/view/Deployment/CLMProductAPILanding
For ETM/RQM, there are several APIs, Reportable REST, OSLC, Module API, Server APIs.
The Reportable REST API allows to create/update ETM/RQM data.
Maybe you consider to understand what Items you want to deal with and then have a look at the data for exemplars that are archived. I would assume that "archived" is just some kind of attribute/flag data. Use appropriate APIs from the set I mention above and GET the archived data to confirm the difference between archived and not archived data.
Once you know the difference use that API and PUT the data modified to not be archived.