Retain Unified Archiving 4.x
Searching is not working.
Indexes do not appear to be updating. In the current Indexing log file, seeing the following:
SolrCloudServerManager: Reloading collection did not complete successfully return code = 404
Unable to access the Indexing HPI web page, page not found error.
The Indexer is not running.
First recommendation is to re-install the same version of Retain over the top of the current installation.
After the installation, check and see if indexing appears to be running or not.