From the Knowledge base:
# Error �1722. There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected� occurs when installing Mathcad.
Cause: This error generally occurs while trying to upgrade the Mathcad 14.0 from one datecode to another. Moreover is a generic Windows Installer error and is encountered for wide range of windows based products.
Solution: From Add/Remove programs, Un-install Mathcad 14, Mathcad 14 Help and Mathcad 14 Resource center. Latest datecode Mathcad 14.0 can be found here
http://www.ptc.com/support/mathcad_downloads.htmNote:
Windows Vista users may uninstall using Programs and Features located in Control Panel.
Richard