| Name | ZZQNDmkumA9nsSi4ap6QjLDmwznN0nGgGQJmIVkRDmzKmKDmRIXC9m_1 |
| Workunit | 239123304 |
| Created | 12 Feb 2026, 18:27:53 UTC |
| Sent | 12 Feb 2026, 18:46:44 UTC |
| Report deadline | 20 Feb 2026, 18:46:44 UTC |
| Received | 12 Feb 2026, 23:36:01 UTC |
| Server state | Over |
| Outcome | Computation error |
| Client state | Compute error |
| Exit status | -2147467259 (0x80004005) Unknown error code |
| Computer ID | 10847220 |
| Run time | 21 sec |
| CPU time | 0 sec |
| Priority | 28 |
| Validate state | Invalid |
| Credit | 0.00 |
| Device peak FLOPS | 42.62 GFLOPS |
| Application version | ATLAS Simulation v3.03 (vbox64_mt_mcore_atlas) windows_x86_64 |
| Peak working set size | 11.73 MB |
| Peak swap size | 6.24 MB |
| Peak disk usage | 651.85 MB |
<core_client_version>7.24.1</core_client_version>
<![CDATA[
<message>
Erro n�o especificado
(0x80004005) - exit code 2147500037 (0x80004005)</message>
<stderr_txt>
2026-02-12 19:35:34 (4440): vboxwrapper version 26210
2026-02-12 19:35:34 (4440): BOINC client version: 7.24.1
2026-02-12 19:35:35 (4440): Detected: VirtualBox VboxManage Interface (Version: 7.0.6)
2026-02-12 19:35:36 (4440): Successfully copied 'init_data.xml' to the shared directory.
2026-02-12 19:35:36 (4440): Create VM. (boinc_063faedf0728923f, slot#1)
2026-02-12 19:35:36 (4440): Setting Memory Size for VM. (4800MB)
2026-02-12 19:35:37 (4440): Setting CPU Count for VM. (8)
2026-02-12 19:35:37 (4440): Setting Chipset Options for VM.
2026-02-12 19:35:37 (4440): Setting Graphics Controller Options for VM. (Driver: VBoxVGA, 16MB)
2026-02-12 19:35:37 (4440): Setting Boot Options for VM.
2026-02-12 19:35:38 (4440): Setting Network Configuration for NAT. (Driver: virtio)
2026-02-12 19:35:38 (4440): Enabling VM Network Access.
2026-02-12 19:35:38 (4440): Disabling USB Support for VM.
2026-02-12 19:35:39 (4440): Disabling COM Port Support for VM.
2026-02-12 19:35:39 (4440): Disabling LPT Port Support for VM.
2026-02-12 19:35:39 (4440): Disabling Audio Support for VM.
2026-02-12 19:35:39 (4440): Disabling Clipboard Support for VM.
2026-02-12 19:35:40 (4440): Disabling Drag and Drop Support for VM.
2026-02-12 19:35:40 (4440): Adding storage controller(s) to VM.
2026-02-12 19:35:40 (4440): Adding virtual disk drive to VM. (ATLAS_vbox_3.03_image.vdi)
2026-02-12 19:35:42 (4440): Adding VirtualBox Guest Additions to VM.
2026-02-12 19:35:43 (4440): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2026-02-12 19:35:43 (4440): forwarding host port 51829 to guest port 80
2026-02-12 19:35:43 (4440): Enabling remote desktop for VM.
2026-02-12 19:35:43 (4440): Required extension pack not installed, remote desktop not enabled.
2026-02-12 19:35:43 (4440): Enabling shared directory for VM.
2026-02-12 19:35:44 (4440): Starting VM using VBoxManage interface. (boinc_063faedf0728923f, slot#1)
2026-02-12 19:35:47 (4440): Error in start VM for VM: -2147467259
Command:
VBoxManage -q startvm "boinc_063faedf0728923f" --type headless
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_063faedf0728923f" to power on...
2026-02-12 19:35:47 (4440): VM failed to start.
2026-02-12 19:35:47 (4440): Could not start
2026-02-12 19:35:47 (4440): ERROR: VM failed to start
2026-02-12 19:35:47 (4440): Powering off VM.
2026-02-12 19:35:47 (4440): Deregistering VM. (boinc_063faedf0728923f, slot#1)
2026-02-12 19:35:47 (4440): Removing network bandwidth throttle group from VM.
2026-02-12 19:35:47 (4440): Removing VM from VirtualBox.
Hypervisor System Log:
00:00:07.618360 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 1 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:07.619148 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 1 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:07.619202 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.619286 Saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:07.622082 Finished saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml"
00:00:07.622203 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.622225 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.622301 Saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:07.624855 Finished saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml"
00:00:07.625172 Saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox" with version "1.19-windows"
00:00:07.628103 Finished saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox"
00:00:07.883935 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.885281 Saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox" with version "1.19-windows"
00:00:07.887878 Finished saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox"
00:00:08.147647 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.149682 Saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox" with version "1.19-windows"
00:00:08.161151 Finished saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox"
00:00:08.665778 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.667107 Saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox" with version "1.19-windows"
00:00:08.668902 Finished saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox"
00:00:08.933007 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.934298 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={Ńo extension pack providing a cryptographic support module could be found}, preserve=false aResultDetail=0
00:00:08.937234 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:08.937287 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:08.941129 ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:09.191633 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.195157 Launched VM: 3915665120 pid: 16884 (0x41f4) frontend: headless name: boinc_063faedf0728923f
00:00:12.421537 Saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox" with version "1.19-windows"
00:00:12.424214 Finished saving settings file "C:\ProgramData\BOINC\slots\1\boinc_063faedf0728923f\boinc_063faedf0728923f.vbox"
00:00:12.462411 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:12.463376 ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:12.495758 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:12.749437 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:12.749603 ERROR [COM]: aRC=VBOX_E_INVALID_OBJECT_STATE (0x80bb0007) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={Cannot unregister the machine 'boinc_063faedf0728923f' while it is locked}, preserve=false aResultDetail=0
00:00:14.008610 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.008817 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.008912 Saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:14.012165 Finished saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml"
00:00:14.012285 Saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:14.013969 Finished saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml"
00:00:14.014733 DeleteVM Saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:14.017332 DeleteVM Finished saving settings file "C:\Users\Valérinha\.VirtualBox\VirtualBox.xml"
00:00:19.028177 main VirtualBox: object deletion starts
00:00:19.028779 main HostDnsMonitor: shutting down ...
00:00:19.028795 main HostDnsMonitor: shut down
00:00:19.029620 Watcher ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:19.029836 main VirtualBox: object deleted
VM Execution Log:
VM Startup Log:
VM Trace Log:
="off"
audio_in="off"
clipboard="disabled"
draganddrop="disabled"
vrde="off"
usb="off"
ehci="off"
xhci="off"
recording_enabled="off"
recording_screens=1
rec_screen0
rec_screen_enabled="on"
rec_screen_id=0
rec_screen_video_enabled="on"
rec_screen_audio_enabled="off"
rec_screen_dest="File"
rec_screen_dest_filename="C:\\ProgramData\\BOINC\\slots\\1\\boinc_063faedf0728923f\\boinc_063faedf0728923f-screen0.webm"
rec_screen_opts="vc_enabled=true,ac_enabled=false,ac_profile=med"
rec_screen_video_res_xy="1024x768"
rec_screen_video_rate_kbps=512
rec_screen_video_fps=25
description="ZZQNDmkumA9nsSi4ap6QjLDmwznN0nGgGQJmIVkRDmzKmKDmRIXC9m_1"
GuestMemoryBalloon=0
2026-02-12 19:35:38 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --nic1 nat --nic-type1 "virtio" --cable-connected1 off --nat-dns-proxy1 on
Exit Code: 0
Output:
2026-02-12 19:35:38 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --cable-connected1 on
Exit Code: 0
Output:
2026-02-12 19:35:39 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --usb off
Exit Code: 0
Output:
2026-02-12 19:35:39 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --uart1 off --uart2 off
Exit Code: 0
Output:
2026-02-12 19:35:39 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --lpt1 off --lpt2 off
Exit Code: 0
Output:
2026-02-12 19:35:39 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --audio-enabled off
Exit Code: 0
Output:
2026-02-12 19:35:40 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --clipboard disabled
Exit Code: 0
Output:
2026-02-12 19:35:40 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --draganddrop disabled
Exit Code: 0
Output:
2026-02-12 19:35:40 (4440):
Command: VBoxManage -q storagectl "boinc_063faedf0728923f" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:
2026-02-12 19:35:41 (4440):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
UUID: 3e56213b-898f-4e83-899f-8eb541d45260
Parent UUID: base
State: created
Type: multiattach
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 4204 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2026-02-12 19:35:41 (4440):
Command: VBoxManage -q storageattach "boinc_063faedf0728923f" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot attach medium 'C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi': the media type 'MultiAttach' can only be attached to machines that were created with VirtualBox 4.0 or later
VBoxManage.exe: error: Details: code VBOX_E_INVALID_OBJECT_STATE (0x80bb0007), component SessionMachine, interface IMachine, callee IUnknown
VBoxManage.exe: error: Context: "AttachDevice(Bstr(pszCtl).raw(), port, device, DeviceType_HardDisk, pMedium2Mount)" at line 785 of file VBoxManageStorageController.cpp
2026-02-12 19:35:41 (4440):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
UUID: 3e56213b-898f-4e83-899f-8eb541d45260
Parent UUID: base
State: created
Type: multiattach
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 4204 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2026-02-12 19:35:41 (4440):
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
2026-02-12 19:35:42 (4440):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
UUID: 3e56213b-898f-4e83-899f-8eb541d45260
Parent UUID: base
State: created
Type: normal (base)
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 4204 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2026-02-12 19:35:42 (4440):
Command: VBoxManage -q storageattach "boinc_063faedf0728923f" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
2026-02-12 19:35:42 (4440):
Command: VBoxManage -q storageattach "boinc_063faedf0728923f" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium none
Exit Code: 0
Output:
2026-02-12 19:35:42 (4440):
Command: VBoxManage -q storageattach "boinc_063faedf0728923f" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
2026-02-12 19:35:43 (4440):
Command: VBoxManage -q storageattach "boinc_063faedf0728923f" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso"
Exit Code: 0
Output:
2026-02-12 19:35:43 (4440):
Command: VBoxManage -q bandwidthctl "boinc_063faedf0728923f" add "boinc_063faedf0728923f_net" --type network --limit 1024G
Exit Code: 0
Output:
2026-02-12 19:35:43 (4440):
Command: VBoxManage -q modifyvm "boinc_063faedf0728923f" --natpf1 ",tcp,127.0.0.1,51829,,80"
Exit Code: 0
Output:
2026-02-12 19:35:43 (4440):
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 0
2026-02-12 19:35:44 (4440):
Command: VBoxManage -q sharedfolder add "boinc_063faedf0728923f" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\1/shared"
Exit Code: 0
Output:
2026-02-12 19:35:47 (4440):
Command: VBoxManage -q startvm "boinc_063faedf0728923f" --type headless
Exit Code: -2147467259
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_063faedf0728923f" to power on...
2026-02-12 19:35:47 (4440):
Command: VBoxManage -q snapshot "boinc_063faedf0728923f" list
Exit Code: -108
Output:
This machine does not have any snapshots
2026-02-12 19:35:47 (4440):
Command: VBoxManage -q bandwidthctl "boinc_063faedf0728923f" remove "boinc_063faedf0728923f_net"
Exit Code: 0
Output:
VBoxManage.exe: error: Bandwidth groups cannot be deleted while the VM is running
2026-02-12 19:35:48 (4440):
Command: VBoxManage -q unregistervm "boinc_063faedf0728923f" --delete
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot unregister the machine 'boinc_063faedf0728923f' while it is locked
VBoxManage.exe: error: Details: code VBOX_E_INVALID_OBJECT_STATE (0x80bb0007), component MachineWrap, interface IMachine, callee IUnknown
VBoxManage.exe: error: Context: "Unregister(fDeleteAll ? CleanupMode_DetachAllReturnHardDisksAndVMRemovable :CleanupMode_DetachAllReturnHardDisksOnly, ComSafeArrayAsOutParam(aMedia))" at line 236 of file VBoxManageMisc.cpp
2026-02-12 19:35:49 (4440):
Command: VBoxManage -q unregistervm "boinc_063faedf0728923f" --delete
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
2026-02-12 19:35:54 (4440): called boinc_finish(-2147467259)
</stderr_txt>
]]>
©2026 CERN