Thanks to your post I was finally able to get Unison working again. I’ve been using it for years but it broke recently after upgrading Cygwin. I fixed that but then needed to install Unison 2.48.3 on the remote server. Your instructions worked up until “sudo cp -v unison /usr/local/sbin/”. For some reason I was getting an error about dangling symlinks and it seemed that a symlink was being created and not the executable being copied. I followed the accepted answer here http://goo.gl/CjQXia and it finally worked.

yum install ocaml ocaml-camlp4-devel ctags ctags-etags
cd ~
wget -> take the link from here http://www.seas.upenn.edu/~bcpierce/unison/download/releases/stable/
For example:
wget http://www.seas.upenn.edu/~bcpierce/unison//download/releases/stable/unison-2.48.3.tar.gz
Extract the file for example:
tar xvfz unison-2.48.3.tar.gz
Enter to the created directory:
cd unison-2.48.3.tar.gz
make
sudo cp -v unison /usr/local/sbin/
sudo cp -v unison /usr/bin
cd ~
rm -fr unison*

Thanks @PhiIT for such a nice explanation. I have quoted your comment at a few places where people were asking the difference between rsync and Unison.

Keep connected!

Thanks @Ulath for your feedback.
Keep connected for more such posts.

You should go through the comment of PhiIT. He nicely explained the difference between rsync and Unison. Unison is not rsync+gui. Here you may like to go through: http://www.tecmint.com/file-synchronization-in-linux-using-unison/comment-page-1/#comment-639635