Took me half day to get Efax-gtk installed on CentOS 7 x64. I am very new to Linux. You must forgive me for I am using incorrect words/syntax or how to explain this. Main reason that it does not find c++-gtk-utils packages because CentOS 7 x64 PATH for pkgconfig is at /usr/lib64/pkgconfig. export PKG_CONFIG_PATH=/usr/lib64/pkgconfig You may need to install libtiff-devel for tiffio.h error at ./configure and export PATH as well. export PATH=$PATH:/usr/include If efax-gtk complains about missing libcxx-gtk-utils...