Quote:Microsoft has recently confirmed that it set a compatibility hold on a series of older Apple Mac devices trying to update to Windows 10 May 2019 Update, or version 1903.
 
Macs can run Windows 10 via Boot Camp, but according to Microsoft, an issue with the Mac HAL driver blocks models prior to 2012 or newer devices with older Boot Camp software from receiving the new feature update.
 
“If you are trying to update to the May 2019 Feature Update for Windows 10 (Windows 10, version 1903), you may experience an update compatbility hold and receive the message, "Mac HAL Driver - machaldriver.sys: Your PC has a driver or service that isn't ready for this version of Windows 10,” Microsoft explains in a support document (via Neowin).
“Mac devices prior to 2012 or newer Mac devices with the older Apple Boot Camp or Windows Support Software drivers have a compatibilty hold in place and are unable to update to Windows 10, version 1903. Specifically, devices with MacHALDriver.sys dated September 24, 2011 01:57:09 or older in Windows\system32\drivers are affected.”