Chosen Solution My iMac keeps shutting down for no reason, saying it shut down because of a problem. Here is the crash report. Machine-check capabilities: 0x0000000001000c0a family: 6 model: 71 stepping: 1 microcode: 33 signature: 0x40671 Intel(R) Core(TM) i5-5675R CPU @ 3.10GHz 10 error-reporting banks Processor 0: IA32_MCG_STATUS: 0x0000000000000005 IA32_MC0_STATUS(0x401): 0xb200000000090005 mp_kdp_enter() timed-out on cpu 0, NMI-ing mp_kdp_enter() NMI pending on cpus: 0 1 2 3 mp_kdp_enter() timed-out during locked wait after NMI;expected 4 acks but received 1 after 13234669 loops in 1546420321 ticks panic(cpu 0 caller 0xffffff8008865b2c): “Machine Check at 0xffffff8008877a83, registers:\n” “CR0: 0x000000008001003b, CR2: 0x0000000116965000, CR3: 0x000000000ca33000, CR4: 0x00000000003626e0\n” “RAX: 0x0000000000000033, RBX: 0x0000000000000000, RCX: 0x0000000000000001, RDX: 0x0000000000000000\n” “RSP: 0xffffff911b553ef0, RBP: 0xffffff911b553f20, RSI: 0xffffff80091f52c0, RDI: 0xffffff8009058390\n” “R8: 0x0000000000000000, R9: 0x0000000000000000, R10: 0x0000000000000008, R11: 0x0000000000000000\n” “R12: 0x0000000000000033, R13: 0x000000000010f527, R14: 0x0000000dbb9b0e14, R15: 0x0000000000000000\n” “RFL: 0x0000000000000046, RIP: 0xffffff8008877a83, CS: 0x0000000000000008, SS: 0x0000000000000010\n” “Error code: 0x0000000000000000\n”@/BuildRoot/Library/Caches/com....