I had some trouble finding a good guide to install steemd on Ubuntu 14.04 64-bit. Here are the commands I used to make it work (most are from https://steem.io/documentation/how-to-build/):
apt-get install software-properties-common
add-apt-repository ppa:ubuntu-toolchain-r/test
apt-get update
export BOOST_ROOT=$HOME/opt/boost_1_60_0
apt install autotools-dev build-essential g++ libbz2-dev libicu-dev python-dev
wget -c 'http://sourceforge.net/projects/boost/files/boost/1.60.0/boost_1_60_0.tar.bz2/download' -O boost_1_60_0.tar.bz2
tar xjf boost_1_60_0.tar.bz2
cd boost_1_60_0/
./bootstrap.sh "--prefix=$BOOST_ROOT"
./b2 install
apt install gcc-4.9 g++-4.9 cmake make libbz2-dev libdb++-dev libdb-dev libssl-dev openssl doxygen libreadline-dev autoconf libtool git libncurses5-dev
cd ~
git clone https://github.com/steemit/steem
cd steem
git submodule update --init --recursive
cmake -DBOOST_ROOT="$BOOST_ROOT" -DCMAKE_BUILD_TYPE=Release .
make
TROUBLESHOOTING
If you still get an error, try
rm CMakeCache.txt in ~/steem/