Name Theory_2914-4711249-41_0
Workunit 232933830
Created 8 Jun 2025, 10:01:16 UTC
Sent 8 Jun 2025, 16:32:37 UTC
Report deadline 19 Jun 2025, 16:32:37 UTC
Received 8 Jun 2025, 20:46:55 UTC
Server state Over
Outcome Computation error
Client state Compute error
Exit status -2147467259 (0x80004005) Unknown error code
Computer ID 10751443
Run time 19 sec
CPU time
Validate state Invalid
Credit 0.00
Device peak FLOPS 1.97 GFLOPS
Application version Theory Simulation v300.95 (vbox64_theory)
windows_x86_64
Peak working set size 11.42 MB
Peak swap size 6.42 MB
Peak disk usage 1.09 MB

Stderr output

<core_client_version>8.0.4</core_client_version>
<![CDATA[
<message>
Unbekannter Fehler
 (0x80004005) - exit code 2147500037 (0x80004005)</message>
<stderr_txt>
2025-06-08 21:45:43 (7544): vboxwrapper version 26210
2025-06-08 21:45:43 (7544): BOINC client version: 8.0.4
2025-06-08 21:45:48 (7544): Detected: VirtualBox VboxManage Interface (Version: 7.1.6)
2025-06-08 21:45:48 (7544): Detected: Heartbeat check (file: 'heartbeat' every 1800.000000 seconds)
2025-06-08 21:45:48 (7544): Successfully copied 'init_data.xml' to the shared directory.
2025-06-08 21:45:48 (7544): Successfully copied 'input' to the shared directory.
2025-06-08 21:45:49 (7544): Create VM. (boinc_8a39c73795770501, slot#2)
2025-06-08 21:45:50 (7544): Setting Memory Size for VM. (630MB)
2025-06-08 21:45:50 (7544): Setting CPU Count for VM. (1)
2025-06-08 21:45:50 (7544): Setting Chipset Options for VM.
2025-06-08 21:45:51 (7544): Setting Graphics Controller Options for VM. (Driver: VBoxVGA, 16MB)
2025-06-08 21:45:51 (7544): Setting Boot Options for VM.
2025-06-08 21:45:52 (7544): Setting Network Configuration for NAT. (Driver: virtio)
2025-06-08 21:45:53 (7544): Enabling VM Network Access.
2025-06-08 21:45:53 (7544): Disabling USB Support for VM.
2025-06-08 21:45:54 (7544): Disabling COM Port Support for VM.
2025-06-08 21:45:54 (7544): Disabling LPT Port Support for VM.
2025-06-08 21:45:54 (7544): Disabling Audio Support for VM.
2025-06-08 21:45:55 (7544): Disabling Clipboard Support for VM.
2025-06-08 21:45:55 (7544): Disabling Drag and Drop Support for VM.
2025-06-08 21:45:55 (7544): Adding storage controller(s) to VM.
2025-06-08 21:45:56 (7544): Adding virtual disk drive to VM. (Theory_2025_04_17_prod.vdi)
2025-06-08 21:46:00 (7544): Adding VirtualBox Guest Additions to VM.
2025-06-08 21:46:00 (7544): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2025-06-08 21:46:00 (7544): forwarding host port 58678 to guest port 80
2025-06-08 21:46:01 (7544): Enabling remote desktop for VM.
2025-06-08 21:46:02 (7544): Enabling shared directory for VM.
2025-06-08 21:46:03 (7544): Starting VM using VBoxManage interface. (boinc_8a39c73795770501, slot#2)
2025-06-08 21:46:14 (7544): Error in start VM for VM: -2147467259
Command:
VBoxManage -q startvm "boinc_8a39c73795770501" --type headless
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_8a39c73795770501" to power on...

2025-06-08 21:46:14 (7544): VM failed to start.
2025-06-08 21:46:14 (7544): Could not start 
2025-06-08 21:46:14 (7544): ERROR: VM failed to start
2025-06-08 21:46:14 (7544): Powering off VM.
2025-06-08 21:46:14 (7544): Deregistering VM. (boinc_8a39c73795770501, slot#2)
2025-06-08 21:46:14 (7544): Removing network bandwidth throttle group from VM.
2025-06-08 21:46:15 (7544): Removing VM from VirtualBox.

    Hypervisor System Log:

00:00:15.491567          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.491766          Saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:15.549761          Finished saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml"
00:00:15.551401          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:15.604675          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:15.960902          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.966112          Platform architecture set to 'x86'
00:00:15.972823          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:16.012721          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:16.223806          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:16.231379          Platform architecture set to 'x86'
00:00:16.240355          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:16.300247          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:17.122632          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:17.129613          Platform architecture set to 'x86'
00:00:17.137296          VRDE: Generating certificate files 'C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\VRDEAutoGeneratedCert.pem' and 'C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\VRDEAutoGeneratedPrivateKey.pem'...
00:00:17.577490          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:17.634264          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:17.964434          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:17.968935          Platform architecture set to 'x86'
00:00:17.974344          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:18.035339          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:18.276626          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:18.281089          Platform architecture set to 'x86'
00:00:18.288321          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={d644ad1e-c501-4fc7-9ab6-aa6d763bc540} aComponent={VirtualBoxWrap} aText={&#197;&#131;o extension pack providing a cryptographic support module could be found}, preserve=false aResultDetail=0
00:00:18.315737          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:18.316020          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:18.342818          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={bea3ef5c-de2f-4b74-aa3a-15d6249371a0} aComponent={RecordingSettingsWrap} aText={Recording not started}, preserve=false aResultDetail=0
00:00:18.345862          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:18.555487          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:18.597873          Launched VM: 3011889552 pid: 11420 (0x2c9c) frontend: headless name: boinc_8a39c73795770501
00:00:26.730220          Platform architecture set to 'x86'
00:00:29.586615          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:29.626969          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:29.870411          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:29.877275          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:30.076251          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:30.082241          Platform architecture set to 'x86'
00:00:30.089632          Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox" with version "1.19-windows"
00:00:30.143587          Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_8a39c73795770501\boinc_8a39c73795770501.vbox"
00:00:30.349746          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:30.351273          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:30.351514          Saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:30.398953          Finished saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml"
00:00:30.399568          Saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:30.474343          Finished saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml"
00:00:30.486153 DeleteVM Saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:30.557068 DeleteVM Finished saving settings file "C:\Users\cbrom\.VirtualBox\VirtualBox.xml"
00:00:35.604805 main     VirtualBox: object deletion starts
00:00:35.612379 main     HostDnsMonitor: shutting down ...
00:00:35.612985 main     HostDnsMonitor: shut down
00:00:35.626237 Watcher  ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={d644ad1e-c501-4fc7-9ab6-aa6d763bc540} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:35.627396 main     VirtualBox: object deleted

    VM Execution Log:


    VM Startup Log:


    VM Trace Log:

"off"
usb="off"
ehci="off"
xhci="off"
recording_started="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\\2\\boinc_8a39c73795770501\\boinc_8a39c73795770501-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="Theory_2914-4711249-41_0"
GuestMemoryBalloon=0

2025-06-08 21:45:53 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --nic1 nat --nic-type1 "virtio" --cable-connected1 off --nat-dns-proxy1 on 
Exit Code: 0
Output:

2025-06-08 21:45:53 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --cable-connected1 on 
Exit Code: 0
Output:

2025-06-08 21:45:54 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --usb off 
Exit Code: 0
Output:

2025-06-08 21:45:54 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --uart1 off --uart2 off 
Exit Code: 0
Output:

2025-06-08 21:45:54 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --lpt1 off --lpt2 off 
Exit Code: 0
Output:

2025-06-08 21:45:55 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --audio-enabled off 
Exit Code: 0
Output:

2025-06-08 21:45:55 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --clipboard disabled 
Exit Code: 0
Output:

2025-06-08 21:45:55 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --draganddrop disabled 
Exit Code: 0
Output:

2025-06-08 21:45:56 (7544): 
Command: VBoxManage -q storagectl "boinc_8a39c73795770501" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:

2025-06-08 21:45:56 (7544): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           multiattach
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-08 21:45:57 (7544): 
Command: VBoxManage -q storageattach "boinc_8a39c73795770501" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot attach medium 'C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.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 786 of file VBoxManageStorageController.cpp

2025-06-08 21:45:57 (7544): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           multiattach
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-08 21:45:58 (7544): 
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-08 21:45:58 (7544): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           normal (base)
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-08 21:45:58 (7544): 
Command: VBoxManage -q storageattach "boinc_8a39c73795770501" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-08 21:45:59 (7544): 
Command: VBoxManage -q storageattach "boinc_8a39c73795770501" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium none 
Exit Code: 0
Output:

2025-06-08 21:46:00 (7544): 
Command: VBoxManage -q storageattach "boinc_8a39c73795770501" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-08 21:46:00 (7544): 
Command: VBoxManage -q storageattach "boinc_8a39c73795770501" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso" 
Exit Code: 0
Output:

2025-06-08 21:46:00 (7544): 
Command: VBoxManage -q bandwidthctl "boinc_8a39c73795770501" add "boinc_8a39c73795770501_net" --type network --limit 1024G 
Exit Code: 0
Output:

2025-06-08 21:46:01 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --natpf1 ",tcp,127.0.0.1,58678,,80" 
Exit Code: 0
Output:

2025-06-08 21:46:01 (7544): 
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 1
Pack no. 0:   Oracle VM VirtualBox Extension Pack
Version:        6.1.32
Revision:       149290
Edition:        
Description:    Oracle Cloud Infrastructure integration, USB 2.0 and USB 3.0 Host Controller, Host Webcam, VirtualBox RDP, PXE ROM, Disk Encryption, NVMe.
VRDE Module:    VBoxVRDP
Crypto Module:  
Usable:         false
Why unusable:   VBoxExtPackRegister returned VERR_VERSION_MISMATCH, pReg=0000000000000000 ErrInfo='Helper version mismatch - expected 0x30000 got 0x50000'

2025-06-08 21:46:02 (7544): 
Command: VBoxManage -q modifyvm "boinc_8a39c73795770501" --vrde on --vrdeextpack default --vrdeauthlibrary default --vrdeauthtype null --vrdeport 58679 --vrde-property "Security/Method=RDP" 
Exit Code: 0
Output:

2025-06-08 21:46:02 (7544): 
Command: VBoxManage -q sharedfolder add "boinc_8a39c73795770501" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\2/shared"
Exit Code: 0
Output:

2025-06-08 21:46:14 (7544): 
Command: VBoxManage -q startvm "boinc_8a39c73795770501" --type headless
Exit Code: -2147467259
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_8a39c73795770501" to power on...

2025-06-08 21:46:14 (7544): 
Command: VBoxManage -q snapshot "boinc_8a39c73795770501" list 
Exit Code: -108
Output:
This machine does not have any snapshots

2025-06-08 21:46:15 (7544): 
Command: VBoxManage -q bandwidthctl "boinc_8a39c73795770501" remove "boinc_8a39c73795770501_net" 
Exit Code: 0
Output:

2025-06-08 21:46:15 (7544): 
Command: VBoxManage -q unregistervm "boinc_8a39c73795770501" --delete 
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

2025-06-08 21:46:21 (7544): called boinc_finish(-2147467259)

</stderr_txt>
]]>


©2025 CERN