There are circumstances where you may need to use the Advanced Sharing feature. For example, when content doesn't accurately represent the content that exists in the originating source collection. In the Sharing tool, click the Advanced button located at the bottom of the page.
Once you are in the Advanced settings, look for the Purge & Reset button. It is only necessary to do a Purge & Reset if you need to re-crawl the entire collection, as described in the condition above. The entire collection will also be purged from the Solr index, so that when the collection is reset the index will be newly rebuilt.
