Description of problem: mockbuild in an epel8 checkout failed for me with an obscure error: Error: Error downloading packages: Status code: 403 for https://infrastructure.fedoraproject.org/repo/rhel/rhel8/koji/latest/x86_64/RHEL-8-001/non_modular/audit-libs-3.0-0.17.20191104git1c2f876.el8.x86_64.rpm (IP: 38.145.60.16) which was particularly puzzling as I have mock working with a RHEL8 root. It turns out it was due not having a working config linked to /etc/mock/epel-8-x86_64.cfg, only to default.cfg. If there was some sort of error relating to the mock configuration, as there would be with plain mock, I'd have spotted the problem rather sooner. Some explicit instruction what to do would be better, though. Version-Release number of selected component (if applicable): 1.41-2.el8 and mock-core-configs-37-1.el8