When I upgraded to F28, OwnCloud stopped working. Another reported the same problem with NextCloud. The problem has been reported in bugzilla [1] as Cannot login after upgrading from F27 to F28. Patrick Reeb provided a fix with a fix-owncloud [2] script which downgrades php-sabre to F25. 

Because both of the Fedora packages of OwnCloud and NextCloud are dated I decided to use the NextCloud zip package of their current version 13. 

Basically what I did was to install Fedora's NextCloud package to get the basic configuration files and then removed the package so all what was left was configuration files with a .rpmsave extension. Using the nextcloud-13.0.4.zip package [3] I moved the files to my nextcloud directory from the Fedora's package.

After a few tweaks to /etc/httpd/conf/httpd.conf files, the login prompt appeared on my localhost/nextcloud.  I was unable to configure my postgresql database from the web browser, so I used the command line tool [4] (occ) to finish the install. 

I did try the snap install of the nextcloud-server, but couldn't get it to work. However, the snap nextcloud-client works like a charm. 

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1562949
[2] https://bugzilla.redhat.com/attachment.cgi?id=1431595
[3] https://nextcloud.com/install/#instructions-server
[4] https://nextcloud.com/install/#instructions-server

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