Hello @merp,
When uploading from KMC, there is a limit of 2G per file.
If the files are bigger than that, you will need to either use the bulk upload service to upload a CSV/XML which includes the URL for the source video and some metatada [you can find an example by going to KMC->Upload menu->selecting "Entries CSV/XML" and clicking on "Download CSV/XML Samples"] or by setting up a dropfolder [see https://knowledge.kaltura.com/kaltura-drop-folders-service-content-ingestion-0] or by utilising the chunked upload mechanism and the JS code hosted here:
If the file is smaller than 2G and the batch job failed, I suggest you go to http://jessex/admin_console/index.php/batch/entry-investigation, input the entry ID and see exactly what failed in the process. You can also request an entry reconversion from that view.