Font keeps changing back to Calibri?

I see this is an old string. Apparently I am late to the conversion. For the record, our organization will never ever recover the time and efficiency already lost in our converion from MS 2003 to MS 2010.  Only the rare office power user will find beneift in conversion. For the vast majority of us 2010 is a costly handicap.

When the normal paragraph style has different settings than the defaults, there is a paragraph style version of normal and the defaults version of normal. When a user applies normal to text, the paragraph settings get applied.  When Word applies normal, such as during a paste or insert, and there is a third version of normal involved, Word will paste or insert the defaults version of normal. In effect, Use destination styles is working, just not the way you want it to.

You had fewer problems in earlier versions because the hard-coded defaults were TNR 12 single spaced, no paragraph spacing--and so no conflict.   But that was by no means the  experience of  users who wanted to use Arial, Univers, or Garamond, use 1.5 spacing, or 14 pts space after.  I got unwanted TNR almost every time I wasn't using TNR.  Because of the mismatch between normal and the defaults, many Word document developers avoid any using normal, others also avoid  using any built-in styles.  That MS remained mum about the problem didn't help either.

The modifiable document defaults does add more steps to the process, particularly for those who are using older documents and templates. But they give us the power to eliminate wrong font pasting issues and several more.

I'm a freelancer who works to deadlines on client-formatted documents that I did not create (yes, some from the government too).  Invariably, the wrong  font shows up after a paste or in the tables.  (The usual practice to avoid the bad paste is to use paste unformatted text (Keep text only in Word's new-speak), and I use it most of the time. But  I often need to keep character formatting and have to use a regular paste.) And invariably, when I check the defaults in these client documents, I see that they are different from the normal paragraph style settings and that it is the defaults that showed up instead of  the normal paragraph font.  In about a minute I make normal and the defaults match. That eliminates the pasting and table problems; I  get to concentrate issues my client wants me to; and along with improved content, I return a document that is structurally in better shape than when I got it.      

 I understand that you really don't want to have to learn this stuff.  But following the steps I described in normal.dotm and other templates you create will mean many fewer surprises at crunch time.

The Manage Styles button is the third from the left of the three buttons in the bottom left corner. This is true in both Word 2007 and Word 2010. If you have a different version, then the procedure will be different.

Excuse my breaking in, here, but I just wanted to thank you, Stefan.  Your second solution, modifhying Normal.dotm directly worked for me (at last!) and opened my eyes. This may help you, too, alsdx.  What I realized is that I had changed my default files folders to a personal folder where all my work is stored (and more easily backed up).  I had to hunt for Normal.dotm, but as soon as I modified it, all new documents suddenly opened in the new normal.