Unable to merge Word document into single PDF and other MS Word issues

Using: Adobe Acrobat Pro 9 Extended & Microsoft Word 2010 & 64-bit Dell laptop with Window 7

Problems exist only after upgrading from a desktop to a laptop (using the same software):

Problem 1. Drag and drop word documents into "combine files" option, after click "combine files", it starts to run, but instead of converting all word documents into one PDF, word documents pop up one by one with a window asking me to "save as", so it is asking me to save each PDF into a different location instead of combining them together.

Problem 2. In window explorer, I used to just right click on any file and choose "convert to Adobe PDF", then it will started immediately and saved the file in the same location. NOW using the new laptop, this function no longer works properly, every time I do the above, the window pops up and asked me to save as somewhere.

It is very annoying as it's a lot more time consuming for simple task which can be done with just one click.

Is there any setting in either MS WORD or ADOBE that I had missed? PLEASE HELP!!!!! Thanks!