G'day Nightgem,

Welcome to the Monastery.

Firstly, you can search for errors in perldiag. In this case you'll find:

Perl API version %s of %s does not match %s

(F) The XS module in question was compiled against a different incompatible version of Perl than the one that has loaded the XS module.

So, the fix would be to install File::Sync using the same version of Perl that you want to 'use File::Sync'.

I did a couple of tests and there doesn't appear to be anything intrinsically wrong with installing or loading this module.

Using my current perl:

$ perl -v
... (v5.24.0) built for darwin-thread-multi-2level ...
$ cpan
cpan[1]> install File::Sync
...
  BRIANSKI/File-Sync-0.11.tar.gz
  /usr/bin/make install  -- OK
cpan[2]> q
Lockfile removed.
$ perl -e 'use File::Sync'
$
[download]

After changing to the oldest perl version I have (with perlbrew):

$ perl -v
... (v5.14.2) built for darwin-thread-multi-2level ...
$ cpan
cpan[1]> install File::Sync
...
  BRIANSKI/File-Sync-0.11.tar.gz
  /usr/bin/make install  -- OK
cpan[2]> q
Lockfile removed.
$ perl -e 'use File::Sync'
$
[download]