In the latest Intel Graphics Driver installer I get the error "this installation package is not supported by this processor type". Older versions work.
I know my Windows is not the latest but it is still supported by Microsoft until October 8, 2019. Therefore, the latest Intel Graphics Driver should be installable on Windows 10 1703 until at least October 8, 2019. It does not make sense to end support for a Windows version before OFFICIAL Microsoft does. Please update the installer to fix this.
1703 is not supported by Microsoft. https://support.microsoft.com/en-au/help/13853/windows-lifecycle-fact-sheet unless you are enterprise or educational.
You did not specify which graphics you have. What is your processor model number?
Just upgrade to 1809, or 1903 preferably, and the problem is gone: https://www.microsoft.com/en-us/software-download/windows10
And, regarding support, 1703 is not supported by Intel at all: https://downloadcenter.intel.com/download/28991/Intel-Graphics-Windows-10-DCH-Drivers?v=t
It makes no sense to stay on an old/unsupported version of the OS and to try to use the latest driver.