It sounds like Word is automatically substituting Helvetica with a similar font, in this case Arial. This is why you can select Helvetica in Word but other applications cannot find it. To confirm this, you can go to
Tools Options Compatibility and click the
Font Substitution button. It should show that Helvetica has been substituted with another font.
If you want to make Helvetica available to other programs, you will need to
- install the actual Helvetica font file in C:\Windows\Fonts. You can do this by obtaining the font file from a reputable source and then copying it into the Fonts folder.
- Once installed, other programs should be able to find and use the Helvetica font.
If you leave Helvetica selected as the formatting for text in a Word document and then move the document to a computer that has the actual Helvetica font installed, that font will be used instead of the substituted font.