I/O Registers
Hi,
This file should be located in your System Workbench installation in C:\Ac6\SystemWorkbench\plugins\fr.ac6.mcu.ide_1.2.0.201506031829\resources\cmsis\STMicroelectronics_CMSIS_SVD
If it is not there that means probably that, either there was a problem when you installed System Workbench, or that you are not using an up-to-date version.
Did you update your IDE (Help >> Check for Updates...) ? If you generated your project using a recent CubeMX version (needed for having System Workbench project generation) you may have generated a project that your (possibly outdated) version of System Workbench does not yet support...
Bernard