Hi there. I need to add helvetica neue font to my indesign program. I CANNOT substitute it. I have a copy of the text files but cannot get it to instal into my indesign program. I am making factsheets for my job and each team member is taking one document. When I edit a document someone has already done everything is highlighted in orange because it says the font is missing. How do I instal the Helvetica Neue font onto my Indesign program?
Buy and install Helvetica Neue in your system first.
Helvetica Neue is not part of the Adobe Fonts service.
( ACP )
To add some things:
 You need the font files for Helvetica Neue.
 The InDesign application can also see and access font files that are stored in InDesign's application's Fonts folder.
 An individual document can see and access font files in a Document fonts folder that is positioned in the same folder the document is also positioned.
( ACP )
Also, if you purchase from LinoType and your co-worker is using a different version, you will still have the missing font errors.
I'm assuming you are on a Windows machine and some of your teammates are Mac.
Mac has had Helvetica Neue as part of its system install for years, so the originator of your documents probably used that thinking it's a common font across platforms. Sadly, nope.
If this becomes a cost issue, you might need to have a chummy meeting with your teammates. As mentioned, Lionotype is the foundry that licensed the Mac versions, so if you buy from there, you have the best chance for an exact match. If you're working for a company, they should be picking up the cost anyway. 😉
Do NOT download anything you find on the Intertubes.. they are likley pirated hacked versions, or knockoffs that will cause you more trouble than it's worth.
There is one more potential option: the Document Fonts folder which would normally be included when packaging a file. If a folder with that name exists in the same folder with the .indd file, ID will look in that folder for missing fonts and use any it finds for editing that particular file without you needing to install them in the OS. You can add such a folder manually and put fonts into it.
There are some caveats, however. Not all font licenses permit this, and not all font formats are cross-platform compatible, so, for example, if you are on PC and the file was packaged on Mac using the old Mac system font your windows system simply cannot see it. Only OpenType and Windows TrueType fonts will work cross-platform.
When I edit a document someone has already done...
How many "someones" are there?
If it's just one other person, the bottom line is you need to be using the same version, and that other person may need to change for the reasons you've already seen here.
If there are several team members and they all have the same version of Helvetica Neue while you are the only one who doesn't, then talk to your IT department and let them solve it.