How to Fix it:
1. Remove wkhtmltopdf and related package
$ sudo apt-get remove libqt4-dev qt4-dev-tools wkhtmltopdf
$ sudo apt-get autoremove
2. Install requirement package for compiling
$ sudo apt-get install openssl build-essential libssl-dev libxrender-dev git-core libx11-dev libxext-dev libfontconfig1-dev libfreetype6-dev fontconfig -y
3. Clone from git wkhtmltopdf and qt source
$ git clone
git://github.com/wkhtmltopdf/wkhtmltopdf.git wkhtmltopdf
$ mkdir qt-wkhtmltopdf && cd qt-wkhtmltopdf
$ git clone
https://www.github.com/wkhtmltopdf/qt --depth 1 --branch wk_4.8.7 --single-branch .
4. Compile qt
$ sudo ./configure -nomake tools,examples,demos,docs,translations -opensource -prefix "`pwd`" `cat ../wkhtmltopdf/static_qt_conf_base ../wkhtmltopdf/static_qt_conf_linux | sed -re '/^#/ d' | tr '\n' ' '`
$ sudo make -j3
$ sudo make install
5. Compile wkhtmltopdf
$ cd ../wkhtmltopdf
$ sudo ../qt-wkhtmltopdf/bin/qmake
$ sudo make -j3
$ sudo make install
6. Reboot
$ sudo reboot
Reference form :http://www.grobak.net/id/blog/how-fix-wkhtmltopdf-failed-error-code-6
