Unable to save term "Big Honor for Branford's Le Petit Café"
This code works perfectly for me:

$term = (object)array(
  'name' =&gt; "Big Honor for Branford's Le Petit Café",
  'vid' =&gt; 1
);

taxonomy_term_save($term);


No errors, and the term is saved as expected. So it looks like the issue is something to do with your server configuration. Without more details it's impossible to say what that problem might be though.

UPDATE

Turns out this a multibyte encoding issue. Wrapping the string in utf8_encode() will fix it:

$term_name-&gt;name = utf8_encode(urldecode("Big%20Honor%20for%20Branford%27s%20Le%20Petit%20Caf%E9"));