Hope you're having a good day! I want to automatically turn on NUC after turning off mains and just by plugging it back on(not hitting the power button on NUC). I changed the CMOS battery, updated the bios, and selected "power on after power failure". Unfortunately, I couldn't automatically turn it on, so your suggestions would be appreciated.
To me it looks that you did every thing good. Are you removing the Power Adapter while the NUC is ON or OFF? Try to cut the power supply while NUC is ON and then reconnect the power.
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Due to this product being discontinued, Intel Customer Service no longer supports inquiries for it, I am glad to see that fellow community members have the knowledge and they jumped in and helped. You may also find the Discontinued Products website (https://www.intel.com/content/www/us/en/support/discontinued-products.html) website helpful to address your request.
You can get the specifications and verify this product's discontinuance status at the Intel® Product Specifications website > Product Status > "Discontinued". https://ark.intel.com/
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