Memory Not written while Full Screen Mode

[KamuranCANAKLI]

My host is Windows 7 64x
Virtual Machine is working while installed 4.3.18 but now I cant full screen virtual machine when I upgrade 4.3.18 to 4.3.20

error is : Memory not written 0x00000000

What can I do ?

VirtualBox COM Server 4.3.20 r96997 win.amd64 (Nov 24 2014 11:05:59) release log
00:00:00.000000 main Log opened 2014-12-25T07:09:04.355098800Z
00:00:00.000000 main Build Type: release
00:00:00.000000 main OS Product: Windows 7
00:00:00.000000 main OS Release: 6.1.7601
00:00:00.000000 main OS Service Pack: 1
00:00:00.046800 main DMI Product Name: LIFEBOOK AH532/G21
00:00:00.062400 main DMI Product Version:
00:00:00.062400 main Host RAM: 16244MB total, 13544MB available
00:00:00.062400 main Executable: C:\Program Files\Oracle\VirtualBox\VBoxSVC.exe
00:00:00.062400 main Process ID: 5752
00:00:00.062400 main Package type: WINDOWS_64BITS_GENERIC
00:00:00.093600 Loading settings file "C:\Users\Kamuran/.VirtualBox\VirtualBox.xml" with version "1.14-windows"
00:00:00.093600 usbLibDevCfgDrGet: DeviceIoControl 1 fail winEr (31)
00:00:00.780001 HostDnsMonitorProxy: Host's DNS information updated:
00:00:00.826801 VDInit finished
00:00:00.826801 Loading settings file "C:\Users\Kamuran\VirtualBox VMs\Win7_BRM\Win7_BRM.vbox" with version "1.14-windows"
00:00:00.826801 Loading settings file "C:\Users\Kamuran\VirtualBox VMs\Win8_BRM\Win8_BRM.vbox" with version "1.14-windows"
00:00:08.705867 ERROR [COM]: aRC=VBOX_E_INVALID_VM_STATE (0x80bb0002) aIID={480cf695-2d8d-4256-9c7c-cce4184fa048} aComponent={Machine} aText={Machine is not locked for session (session state: Unlocked)}, preserve=false
00:00:13.252612 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={3295e6ce-b051-47b2-9514-2c588bfe7554} aComponent={ExtPackManager} aText={No extension pack by the name 'Oracle VM VirtualBox Extension Pack' was found}, preserve=false
00:00:13.260613 ERROR [COM]: aRC=VBOX_E_IPRT_ERROR (0x80bb0005) aIID={480cf695-2d8d-4256-9c7c-cce4184fa048} aComponent={SessionMachine} aText={Saved screenshot data is not available (VERR_NOT_SUPPORTED)}, preserve=false
00:02:00.788267 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={3295e6ce-b051-47b2-9514-2c588bfe7554} aComponent={ExtPackManager} aText={No extension pack by the name 'Oracle VM VirtualBox Extension Pack' was found}, preserve=false
00:02:00.792268 ERROR [COM]: aRC=VBOX_E_IPRT_ERROR (0x80bb0005) aIID={480cf695-2d8d-4256-9c7c-cce4184fa048} aComponent={SessionMachine} aText={Saved screenshot data is not available (VERR_NOT_SUPPORTED)}, preserve=false
00:02:00.819271 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={3295e6ce-b051-47b2-9514-2c588bfe7554} aComponent={ExtPackManager} aText={No extension pack by the name 'Oracle VM VirtualBox Extension Pack' was found}, preserve=false

[mick.saxton]

I have identical problem if I attempt to go fullscreen on my Windows7 x64 host.
Also if I request "adjust Window Size" it goes to a very small window.

I didn't have this problem on V4.3.12 (could not use the versions in between)

I guess we just use "Maximze" instead of "Fullscreen" until it is fixed.

[mpack]

Minimum information needed for assistance.

[mick.saxton]

Could also try unticking "Mini Toolbar" in Settings -> General -> Advanced

That stopped the crash on "Full screen" for me - but I still have the other size problem.