Unable to install MS PowerPoint 97 Viewer after download.
Note:hlinkprx.dll was unable to register itself in the system
registry. How can I solve this prpblem?

To resolve this problem, follow these steps: 
1. Insert the Office 97 CD-ROM or the Small Business Edition of Office
CD-ROM into your CD-ROM drive.

2. Use Windows Explorer to open the CD-ROM Drive:\OS\System folder,
where CD-ROM Drive is the name of your CD-ROM drive, for example drive
D, and then click the Hlinkprx.dll file.

3. On the Edit menu, click Copy.

4. Use Windows Explorer to open the Windows\System folder on the
computer that you are using to create the disk images.

5. On the Edit menu, click Paste.

6. Use RegSvr32.exe to register the DLL file in the registry. For more
information about how to do so, see the "References" section later in
this article.

7. Start the Setup Wizard, and then create the disk images again.

Reference:
http://support.microsoft.com/default.aspx?scid=kb;en-us;200931