One of the prerequisites for installing SQL Server 2008 Express R2 is Windows Installer 4.5. I have a couple of WS2008 machines I'm prepping, so I downloaded the appropriate version of the file (Windows6.0-KB942288-v2-x86.msu) to our file server and tried installing it on both machines.
On both machines I get the cryptic 0x80070003 error: "the system cannot find the file specified", but it does not show which file it cannot find. I don't get this when I try to install the Windows XP version on one of my XP machines. Any clues as to what I might be missing or doing wrong?
One Technet help forum suggested I try installing the "System Update Readiness Tool", but this installer also fails for the same error code.