Package: libxaw7-dev Version: 2:1.0.8-1 Apparently the dev package contains the library itself. Unpacking libxaw7-dev (from .../libxaw7-dev_2%3a1.0.8-1_amd64.deb) ...dpkg: error processing /var/cache/apt/archives/libxaw7-dev_2%3a1.0.8-1_amd64.deb (--unpack): trying to overwrite '/usr/lib/libXaw.so', which is also in package libxaw7 2:1.0.8-1