This link was sent to me off-list, but I think the intention was to share with those who are having this problem. In short, if your OPAC header is an image file, make sure that image is linked to using a full url, not a relative one: Bad: <img src="my_opac_header.jpg" /> Good: <img src="https://example.com/path_to_my_images/my_opac_header.jpg" /> -- Owen ---------- Forwarded message --------- From: takan bhatt <takan.bhatt@gmail.com> Date: Mon, Dec 17, 2018 at 8:15 AM Subject: Re: [Koha] OPAC header To: Owen Leonard <oleonard@myacpl.org> pls see this https://lists.katipo.co.nz/public/koha/2017-September/048923.html