As noted in a couple of threads, for some people, updating to the PSoC Creator 4.2 production release causes projects to no longer build. Here's what's happening, and how to work around the problem.
The released version of PSoC Creator 4.2 is incompatible with earlier versions of PDL 3.0.1 The updater does not handle this correctly. If you have an earlier version of PDL 3.0.1 installed (from the Beta community, for example), and you update your Creator installation, things break.
We know what caused the problem, and we are working to make sure the root cause is fixed ASAP, but that won't be instantaneous.
Go to the PDL product page, scroll down to the Related Files section, and download the file "Download PDL 3.0.1 Complete Setup.exe" . Run the installer to update your PDL.
Senior Principal Applications Engineer
Message was edited by: James Trudeau, providing an easier workaround now that it's in place.