so the PATH was changed to: PATH=/usr/bin:$PATH

Read more about some conflicts [http://cygwin.com/cygwin-ug-net/using.html#using-pathnames here]

*4- If there was an error applying a patch to a repository e.g. <code> hg import patch12.patch </code>, there might be a problem with line numbers merging issue. So, there will be an error created with this message: "Hunk #1 Failed". There are some ways to remove the hunks manually or just ignore that patch, if the later versions are fixed.

: By "hunk" I mean a "snippet of change", i.e. a part of the "diff". TortoiseHg uses this terminology and so does darcs. – Deniz Dogan

: For Hunk Failed message, first we need to make sure it's not applied before. Second thing to check is that bases are the same. All the revisions before that new changeset even with failed build should be applied before applying the successfully built change-set.