This message was posted on behalf of Intel Corporation
Hi LeoG71: Thank you very much for contacting the Intel® Rapid Storage Technology communities. We will do our best in order to assist you with this scenario.
Just to let you know, the newest version of Intel® RST that the chipset of the board supports is 22.214.171.1241:
That version does not support Windows® Server 2016, according to ASUS’s web site the board does not support server operating systems:
So this could be a compatibility problem and what we suggest in this case will be to re-install the operating system that was working properly before.
Any further questions, please let me know.