Broken links in a PDF file are easy to fix, either in the application in which the original document was created or in Adobe Acrobat. In Adobe's Creative Suite programs, hyperlinks created in InDesign are not active within that program, and can be tested only after exporting the document as a PDF.
Define the link in the original document using the application that created it, such as Microsoft Word, and in the hyperlink menu correct the target address. Export again as a PDF file to replace the previous version.
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Use Acrobat instead if you have only the PDF version of the document or to avoid switching back and forth between applications.
Click on the Links tool, an icon with two links of chain. All existing links will be highlighted with a rectangle in the PDF document.
Double-click on the broken link, and in the Link Properties menu that opens, click on "Open a web link" under "Actions," then click "Edit."
Correct the link address in the "Edit URL" box that opens, then click "OK."
Use the Links tool to add links that did not transfer over from the original document. With the cursor now in the shape of a cross hair, draw a rectangle around the text or object you wish to make a link.
Select the link action "Go to a page view," "Open a file," "Open a web page," or "Custom Link." Click "Next." For a webpage, enter a URL in the box that opens.
For a document you may wish wish to edit further or use again, it's better to fix the link in the original application. That way if you make other changes, all your changes will be exported to the PDF version.