I've created a logo in Illustrator, and before I export it, the spacing looks fine. See below:
But then, once I export it, it doesn't keep the spacing around the letters I want (the right side of the picture looks ok, but the left side has the "M" up against the border):
In the Export dialog box, tick the 'Use Artboards' option. This saves the image including the containing artboard, what you're seeing as the white frame behind your logo.
If you need to re-adjust the white area (the artboard), hit Shift+O and drag the square handles which will appear at the edge of each side or at the corners.
