I've been trying to print my own business cards and uploading a 500dpi resolution to online printing companies but both my own printouts and the image that shows on up the websites' preview are not sharp. It helped that I used a page size of 7" x 4" instead of the actual business card size of 3.5" x 2" and then I just made it smaller in Word but it's still a little blurry. The online printing company's site still shows a poor resolution image. What am I doing wrong?

What format are you exporting it to?

If the whole thing is a vector, then you can try saving it as a pdf or eps (with correct dimensions). That way quality shouldn't be lost. Actually, even if everything wasn't vector, pdf/eps would still be the better way to go.

If you're exporting it as bitmap, then I'm not too sure. There is a resolution/dpi setting when exporting bitmap (I think it is set to 90 as default, so if your document is twice as big as the card, your resolution would only be about 180). Try increasing the resolution value.

yes, to bitmap and i tried increasing the dpi to as high as 500. I'll try the pdf way then. Thanks.

So how big is the resulting bitmap? If you want it to be 3.5" x 2" at 500 DPI then the bitmap should be 1750 x 1000 pixels. If your exported bitmap is not that size then the easiest solution is to use those pixel height and width values when exporting.