I am fairly confident this is not something that happens often, but I am open to be proven wrong. This is most likely a hardware issue, but I really hope it is not.

My mac starts up with a blank white screen. There is no apple logo or error logo. Every one in ten"ish" times it will actually boot up after multiple times turning it off. When I am finally at my home screen it is extremely slow to run applications.(Even more so than it was prior to the problem)

I used command s to find out if there was an error in code, but even then it wouldn't boot-up properly. When I did get it to work it showed this code

Code: AppleUSBMultitouchDriver: IOUSBHostHIDDevice: :start: unable to start IOHIDDevice HID: Legacy shim 2

This repeated many times.

If this is a hardware problem how can I replace the parts inside my Mac? I wanted to replace some of the parts anyway.

If this is a software problem how do I fix it?

Thank you guys,


  • While I am unsure about the error message and if it is indicative of something that is causing the boot failures, it really sounds like a hardware issue. There is a component that is likely failing. Finding that bit will be difficult. Likely you will need to take it to an Apple repair tech, an independent one not an Apple store as they don't do component level repairs and your system may be obsoleted. – Steve Chambers May 3 at 22:10
  • Re 'how can I replace the parts inside my Mac?', ifixit.com is an excellent resource with visual guides for repairing/replacing parts. I wouldn't buy replacement parts at the prices they charge, though, but I do recommend their toolkits. – Richard Brockbank May 4 at 0:02
  • You might try running Apple Hardware Test, though I don't know if would tell you more than you've already found out using Single User Mode. – Richard Brockbank May 4 at 0:06
  • @ScrubsDaBubs did my answer solve your problem? – Sam May 9 at 1:55

From what I understand, I think that this is a trackpad driver issue. Try booting up while holding the Command and R keys, and then re-installing macOS.

If that doesn't fix it, then you may need to install a new trackpad. You can find instructions on how to do this here. As for buying a trackpad, you can probably find one on eBay here, like this one.

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