pgbackrest archive-push exit code 25

I am in the process of getting pgbackrest up and running on my analysis server, and I keep on getting the following but can't find a reference for "exit code 25" in for pgbackrest. My next step will be to restart the server when a current process is done, but beyond that I'm kind of stuck and have a large backlog of WAL at this point, but where do I find a reference for this error code?

2018-05-18 08:54:22.528 MDT [28589] LOG: archive command failed with exit code 25
2018-05-18 08:54:22.528 MDT [28589] DETAIL: The failed archive command was: pgbackrest --stanza=tsbackup archive-push pg_wal/000000010000A7E0000000F5
2018-05-18 08:54:22.529 MDT [28589] WARNING: archiving write-ahead log file "000000010000A7E0000000F5" failed too many times, will try again later

Thanks,
Stephen

________________________________
Stephen Froehlich
Sr. Strategist, CableLabs(r)

s(dot)froehlich(at)cablelabs(dot)com<mailto:s(dot)froehlich(at)cablelabs(dot)com>
Tel: +1 (303) 661-3708