On Wed, December 23, 2015 00:33, John R Pierce wrote: > > prefixing this with, I have no idea what Calibre is... > Calibre is an open source e-reader that handles mobi files along with many other e-reader formats. See: http://calibre-ebook.com/ The last version supported on CentOS6 is v1.48. The latest version is v2.47.0. On Tue, December 22, 2015 22:06, Fred Smith wrote: > Attempting to install latest Calibre on Centos-7, getting: . . . > File "/usr/lib64/python2.7/httplib.py", line 1182, in __init__ > context.load_cert_chain(cert_file, key_file) > ssl.SSLError: [SSL] PEM lib (_ssl.c:2757) > > > Can anybody advise me what this tells me? (other than SOMETHING wrong > with some certificate...) The error you are reporting may be due to some misconfiguration of the certificate chain in the Python libraries. Likely the case if you recently updated to 7.2 as others have reported the same thing. You can try to perform a manual download and install, thus bypassing the whole SSL mess, and see if that works. Quoting from the Calibre website: http://calibre-ebook.com/download_linux Manual binary install or reverting to a previous version If you wish to revert to an earlier calibre release or download a calibre upgrade manually, download the tarball of that release from here (choose the 32-bit or 64-bit version, as appropriate). Assuming you want calibre in /opt/calibre, run the following command, changing the path to calibre-tarball.txz below as appropriate: sudo mkdir -p /opt/calibre && sudo rm -rf /opt/calibre/* && sudo tar xvf /path/to/downloaded/calibre-tarball.txz -C /opt/calibre && sudo /opt/calibre/calibre_postinstall HTH. -- *** e-Mail is NOT a SECURE channel *** Do NOT transmit sensitive data via e-Mail James B. Byrne mailto:ByrneJB at Harte-Lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3