General Mac software discussions forum: Word 2011 files converted to PDFs can't be merged.

If you used the print option>save as PDF, it seems strange because this pdf making is handled by the system, not by Word. If you did it through Acrobat/Reader plugin, it may be prone to all sorts of things up to incomplete file conversion. Another thing to look for would be protection. If each PDF is protected, Acrobat cannot merge the files. If this is the case, revert to generating PDF files through print option or get a program called PDF protect that can either protect PDF files or deprotect them.

I don't have Office 2011 but presume that it has the doc extension when saving Word files. Or is it something other than that? What if the document is saved first as Word 2008 (docx) or 2004 (doc)? Will the resultant files behave abnormally again when converted to pdf? Saving them in older formats might help. It could simply be that some weird encoding prevents Acrobat from merging files or the PDFs are not well encoded due to some subtle incompatibility with OS X PDF converter. On top of that, to ensure compatibility with a wider audience, saving in older formats also helps.

Although I am not fond of that place, you might give it a shot because if they duplicate it, it seems to be a serious bug affecting many users. Concerning the "workarounds", this one is actually not a workaround. Many people still have older versions that do not recognize docx and need a converter. Converters are free but not 100% accurate by some accounts. So, in order to improve capability with other potential users, it would be better to save as doc as a default (very easy to set in a save as dialog box. If that works, I would not look back. After all, if you do not find a workaround, you may be stuck with a relatively useless program (may be no incentive to use it if you have Word 2008).
A remote option would be to trash the Normal file or even reinstall Office (if you find on the forums that others do not have this problem).
Please keep us posted because this is an important issue. I am considering switching to 2011 but am not sure whether they cleaned up the bugs from 2008.
Do you ever insert a ppt picture into Word text box? If yes, do you need to only use paste special and select pdf like in Word 2008 (otherwise it would be fuzzy)?