(Please start new threads for new issues — this has nothing to do with the thread you posted to. I've moved this to a new thread.)
www-cairn-info.[…].idm.oclc.org:443 uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.
This is a problem with your proxy server that will need to be fixed by your IT department (possibly in conjunction with OCLC). Details here:
(I redacted part of the domain above, but you can see it in the Error Console. The full domain shows "Chain Issues: Incomplete" in the SSL Labs test, as explained on the above page.)
Upgrade Storage
I've had this exact same problem for a moment now, I even subscribed to an upgrade storage thinking that it was a storage problem.
I have run the error and the Debug ID is D198734511.
What can I do to fix this pdf dowload problem? I've tried with various documents now and none is working. Is there something I can do?
Thank you so much
https://www.zotero.org/support/kb/incomplete_cert_chain
(I redacted part of the domain above, but you can see it in the Error Console. The full domain shows "Chain Issues: Incomplete" in the SSL Labs test, as explained on the above page.)