id summary reporter owner description type status component version resolution keywords cc guest host 15770 Anniversary update incompatibility / the instuction at ... referenced memory 0x0000000000000020. The memory could not be read Frank Bevers "A quick way of REPLICATING this (for me) on my W10/64bit host with anniversay update & VB up to version 5.1.3 /build 109780 is to simply close a vm window & then select ""power off the machine"" in the popup window. I tested with W7 & W8.1 vm's , even with freshly created vm's. Under normal working circumstances the error occurs USUALLY when I shutdown a vm from within the vm itself (orderly shutdown) I tried reverting to an older build as well (5.0.26) and it has the same issue so it must be an incompatibility caused by the W10 anniversary update I guess." defect closed VM control VirtualBox 5.1.2 fixed Windows Windows