What should I do if I get error message 1603 ("Error Installing Windows Installer engine") during install?

Blog Post created by toleary on Aug 20, 2013

Occasionally, the following error message appears during an install:


"1603: Error installing Windows Installer engine. A file which needs to be replaced may be held in use. Close all applications and try again."


This message is generated by Windows, and can be safely disregarded. Simply click OK to proceed. Blueprint will install successfully.