undefined symbol: OGR_F_SetFieldNull when installing qgis

Question

I tried to re-install qgis on Ubuntu 16.04 LTS (xenial) using the ubuntugis repository (http://qgis.org/ubuntugis) but I get the following error messages which I cannot resolve:

Setting up qgis-providers (1:2.18.13+24xenial-ubuntugis) ...
/usr/lib/qgis/crssync: symbol lookup error: /usr/lib/libqgis_core.so.2.18.13: undefined symbol: OGR_F_SetFieldNull
dpkg: error processing package qgis-providers (--configure):
 subprocess installed post-installation script returned error exit status 127
dpkg: dependency problems prevent configuration of qgis:
 qgis depends on qgis-providers (= 1:2.18.13+24xenial-ubuntugis); however:
  Package qgis-providers is not configured yet.

dpkg: error processing package qgis (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of qgis-plugin-globe:
 qgis-plugin-globe depends on qgis (= 1:2.18.13+24xenial-ubuntugis);     however:
  Package qgis is not configured yet.

dpkg: error processing package qgis-plugin-globe (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of qgis-plugin-grass:
 qgis-plugin-grass depends on qgis (= 1:2.18.13+24xenial-ubuntugis); however:
  Package qgis is not configured yet.

dpkg: error processing package qgis-plugin-grass (--configure):
   No apport report written because the error message indicates its a followup error from a previous failure.
   No apport report written because the error message indicates its a followup error from a previous failure.
   No apport report written because MaxReports is reached already

Errors were encountered while processing:
 qgis-providers
 qgis
 qgis-plugin-globe
 qgis-plugin-grass
E: Sub-process /usr/bin/dpkg returned an error code (1)

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I've purged QGis and GDAL and re-installed everything. Now, It will be installed! However, it won't start because I encounter the same problem mentioned here: gis.stackexchange.com/questions/234010/qgis-fails-to-load/… But the solution (installing scipy 0.17) did not resolve that problem ...

Answer 1

Problem solved! I had some wrong set paths for gdal and the wrong scipy version for python 2.7. I re-installed GDAL, set the paths correct and then downgraded scipy to version 0.17 (note that you downgrade scipy for the python version that is used by qgis, I thought the downgrade had no effect but in fact I've downgraded the scipy version for python 3.5)