SWI-Prolog depends on the MSVC runtime library, currently VC90.CRT.
This library is not shipped with the installer. By default, the
installer tries to detect whether the runtime is available and
installs it from Microsoft if it cannot be detected. There are
two possible issues with this:
- On some systems the automatic install fails, e.g., because
the machine is not attached to the network, uses a proxy, etc.
In that case, install the runtime `somehow' by hand and retry
- On some systems, notably those where Windows is not installed
in the default
C:\windows folder, detection fails. Make sure
that the runtime is installed and uncheck the tickbox Install VC runtimes
in the installer.