There is nothing about the macro itself that would cause that behaviour. Perhaps the document you're running it from has acquired some of corruption. Corrupt documents can often be 'repaired' by inserting a new, empty, paragraph at the very end, copying everything except that new paragraph to a new document based on the same template (macros, userforms, headers & footers may need to be copied separately), closing the old document and saving the new one over it.

Similarly, corrupt tables (which the above process won't repair) can often be 'repaired' by:
• converting the tables to text and back again;
• cutting & pasting them to another document that you save the document in RTF format, which you then close then re-open before copying them back to the source document; or
• saving the document in RTF format, closing the document then re-opening it and re-saving in the doc(x) format.
Do note that some forms of table corruption can only be repaired by the first method.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]