After the latest upgrade from 2.4.0 to 2.4.2, GnuCash fails to start. I get the splash screen and the tips window, both which disappear quickly. Then nothing. I'm running portable apps on a Win Vista PC. I thought it might have been the same issue as I had for 2.4.0 (see recent post Feb 7, GnuCash 2.4 fails to start after upgrade), and tried the suggestions there, but to no avail. This seems to be a different issue.
I've reverted back to 2.4.0 and all is well again.