I had used the examples\peripheral\blinky\pca10040\blank\arm5_no_packs Keil project from nRF-SDK v15.0.0 using Keil MDK v5.25.
EDIT: as described here: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v15.0.0%2Fgetting_started_examples.html&cp=4_0_0_1_2
This was building, downloading, and running fine on the PCA10040 target. board.
So I created a second Target in the Project, adapted for a Fanstel BT832-EVM-V1 kit. This was also building, downloading, and running fine on the BT832-EVM-V1 target board.
Then I installed nRF Connect v2.3.0.
The PCA10040 Target still builds, but the BT832-EVM-V1 Target fails:
*** Using Compiler 'V5.06 update 6 (build 750)', folder: 'C:\bin\Keil\MDK\525\ARM\ARMCC\Bin'
Rebuild target 'bt832-evm-v1'
Error instantiating RTE components
Error #540: 'ARM::CMSIS:CORE:4.3.0' component is not available for target 'bt832-evm-v1', pack 'ARM.CMSIS.4.5.0' is not selected
Target not created.
So why has installing nRF Connect v2.3.0 messed with my Project?
And, more importantly, why has it broken my Project?
How do I fix it?