If security/libressl is installed, the initial contact attempt fails with the error message "Invalid or empty cipher list ()".
quarterly ports tree
I kind of doubt that libressl is supported in any meaningful way. You might ask owncloud upstream.
(In reply to Adriaan de Groot from comment #1)
Thank you for weighing in.
For the purposes of this bug report, I don't think it should matter whether libressl is supported upstream.
I see at two ways to resolve this, and there may be others at the maintainer's discretion:
1) Register a conflict with the libressl port. This option would be easy to implement and yet unsatisfying.
2) Patch owncloudclient so it always uses the SSL libs it was built against and no others that might be available from time to time. This might be hard to implement and would be completely satisfying to me.