| Name | FHKODmXOv98nsSi4ap6QjLDmwznN0nGgGQJmIVkRDmbfhKDmSQnnxn_0 |
| Workunit | 239067696 |
| Created | 10 Feb 2026, 5:33:51 UTC |
| Sent | 10 Feb 2026, 11:00:29 UTC |
| Report deadline | 18 Feb 2026, 11:00:29 UTC |
| Received | 10 Feb 2026, 11:09:07 UTC |
| Server state | Over |
| Outcome | Computation error |
| Client state | Compute error |
| Exit status | -2147467259 (0x80004005) Unknown error code |
| Computer ID | 10795183 |
| Run time | 23 sec |
| CPU time | 0 sec |
| Priority | 28 |
| Validate state | Invalid |
| Credit | 0.00 |
| Device peak FLOPS | 22.97 GFLOPS |
| Application version | ATLAS Simulation v3.03 (vbox64_mt_mcore_atlas) windows_x86_64 |
| Peak working set size | 11.31 MB |
| Peak swap size | 6.42 MB |
| Peak disk usage | 471.82 MB |
<core_client_version>7.24.1</core_client_version>
<![CDATA[
<message>
- exit code 2147500037 (0x80004005)</message>
<stderr_txt>
2026-02-10 18:50:37 (12308): vboxwrapper version 26210
2026-02-10 18:50:37 (12308): BOINC client version: 7.24.1
2026-02-10 18:50:38 (12308): Detected: VirtualBox VboxManage Interface (Version: 7.0.6)
2026-02-10 18:50:38 (12308): Successfully copied 'init_data.xml' to the shared directory.
2026-02-10 18:50:38 (12308): Create VM. (boinc_26e350c5e3892277, slot#0)
2026-02-10 18:50:39 (12308): Setting Memory Size for VM. (4600MB)
2026-02-10 18:50:39 (12308): Setting CPU Count for VM. (6)
2026-02-10 18:50:39 (12308): Setting Chipset Options for VM.
2026-02-10 18:50:39 (12308): Setting Graphics Controller Options for VM. (Driver: VBoxVGA, 16MB)
2026-02-10 18:50:40 (12308): Setting Boot Options for VM.
2026-02-10 18:50:40 (12308): Setting Network Configuration for NAT. (Driver: virtio)
2026-02-10 18:50:41 (12308): Enabling VM Network Access.
2026-02-10 18:50:41 (12308): Disabling USB Support for VM.
2026-02-10 18:50:41 (12308): Disabling COM Port Support for VM.
2026-02-10 18:50:41 (12308): Disabling LPT Port Support for VM.
2026-02-10 18:50:42 (12308): Disabling Audio Support for VM.
2026-02-10 18:50:42 (12308): Disabling Clipboard Support for VM.
2026-02-10 18:50:42 (12308): Disabling Drag and Drop Support for VM.
2026-02-10 18:50:42 (12308): Adding storage controller(s) to VM.
2026-02-10 18:50:43 (12308): Adding virtual disk drive to VM. (ATLAS_vbox_3.03_image.vdi)
2026-02-10 18:50:45 (12308): Adding VirtualBox Guest Additions to VM.
2026-02-10 18:50:45 (12308): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2026-02-10 18:50:45 (12308): forwarding host port 57620 to guest port 80
2026-02-10 18:50:46 (12308): Enabling remote desktop for VM.
2026-02-10 18:50:46 (12308): Required extension pack not installed, remote desktop not enabled.
2026-02-10 18:50:46 (12308): Enabling shared directory for VM.
2026-02-10 18:50:46 (12308): Starting VM using VBoxManage interface. (boinc_26e350c5e3892277, slot#0)
2026-02-10 18:50:51 (12308): Error in start VM for VM: -2147467259
Command:
VBoxManage -q startvm "boinc_26e350c5e3892277" --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_26e350c5e3892277" to power on...
2026-02-10 18:50:51 (12308): VM failed to start.
2026-02-10 18:50:51 (12308): Could not start
2026-02-10 18:50:51 (12308): ERROR: VM failed to start
2026-02-10 18:50:51 (12308): Powering off VM.
2026-02-10 18:50:51 (12308): Deregistering VM. (boinc_26e350c5e3892277, slot#0)
2026-02-10 18:50:51 (12308): Removing network bandwidth throttle group from VM.
2026-02-10 18:50:52 (12308): Removing VM from VirtualBox.
Hypervisor System Log:
00:00:09.215375 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.215385 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.215396 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.225382 Launched VM: 3201385680 pid: 23936 (0x5d80) frontend: headless name: boinc_26e350c5e3892277
00:00:13.955559 Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_26e350c5e3892277\boinc_26e350c5e3892277.vbox" with version "1.19-windows"
00:00:13.959731 Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_26e350c5e3892277\boinc_26e350c5e3892277.vbox"
00:00:14.089401 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.089434 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.089457 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.089475 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.089492 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.091290 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
00:00:14.152692 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.152721 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.152733 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.152742 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.152752 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414387 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414411 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414423 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414434 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414444 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:14.414706 ERROR [COM]: aRC=VBOX_E_INVALID_OBJECT_STATE (0x80bb0007) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={Cannot unregister the machine 'boinc_26e350c5e3892277' while it is locked}, preserve=false aResultDetail=0
00:00:15.678211 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678235 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678248 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678260 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678271 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678676 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678694 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678707 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678717 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678728 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:15.678809 Saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:15.687013 Finished saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml"
00:00:15.687125 Saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:15.690651 Finished saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml"
00:00:15.691616 DeleteVM Saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:15.695014 DeleteVM Finished saving settings file "C:\Users\USER\.VirtualBox\VirtualBox.xml"
00:00:20.704699 main VirtualBox: object deletion starts
00:00:20.705976 main HostDnsMonitor: shutting down ...
00:00:20.706012 main HostDnsMonitor: shut down
00:00:20.707891 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
00:00:20.708298 main VirtualBox: object deleted
VM Execution Log:
VM Startup Log:
VM Trace Log:
isabled"
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\\0\\boinc_26e350c5e3892277\\boinc_26e350c5e3892277-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="FHKODmXOv98nsSi4ap6QjLDmwznN0nGgGQJmIVkRDmbfhKDmSQnnxn_0"
GuestMemoryBalloon=0
2026-02-10 18:50:41 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --nic1 nat --nic-type1 "virtio" --cable-connected1 off --nat-dns-proxy1 on
Exit Code: 0
Output:
2026-02-10 18:50:41 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --cable-connected1 on
Exit Code: 0
Output:
2026-02-10 18:50:41 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --usb off
Exit Code: 0
Output:
2026-02-10 18:50:41 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --uart1 off --uart2 off
Exit Code: 0
Output:
2026-02-10 18:50:42 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --lpt1 off --lpt2 off
Exit Code: 0
Output:
2026-02-10 18:50:42 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --audio-enabled off
Exit Code: 0
Output:
2026-02-10 18:50:42 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --clipboard disabled
Exit Code: 0
Output:
2026-02-10 18:50:42 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --draganddrop disabled
Exit Code: 0
Output:
2026-02-10 18:50:43 (12308):
Command: VBoxManage -q storagectl "boinc_26e350c5e3892277" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:
2026-02-10 18:50:43 (12308):
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
2026-02-10 18:50:43 (12308):
Command: VBoxManage -q storageattach "boinc_26e350c5e3892277" --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
2026-02-10 18:50:43 (12308):
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
2026-02-10 18:50:44 (12308):
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.03_image.vdi"
Exit Code: 0
Output:
2026-02-10 18:50:44 (12308):
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
2026-02-10 18:50:44 (12308):
Command: VBoxManage -q storageattach "boinc_26e350c5e3892277" --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:
2026-02-10 18:50:45 (12308):
Command: VBoxManage -q storageattach "boinc_26e350c5e3892277" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium none
Exit Code: 0
Output:
2026-02-10 18:50:45 (12308):
Command: VBoxManage -q storageattach "boinc_26e350c5e3892277" --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:
2026-02-10 18:50:45 (12308):
Command: VBoxManage -q storageattach "boinc_26e350c5e3892277" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso"
Exit Code: 0
Output:
2026-02-10 18:50:45 (12308):
Command: VBoxManage -q bandwidthctl "boinc_26e350c5e3892277" add "boinc_26e350c5e3892277_net" --type network --limit 1024G
Exit Code: 0
Output:
2026-02-10 18:50:46 (12308):
Command: VBoxManage -q modifyvm "boinc_26e350c5e3892277" --natpf1 ",tcp,127.0.0.1,57620,,80"
Exit Code: 0
Output:
2026-02-10 18:50:46 (12308):
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 0
2026-02-10 18:50:46 (12308):
Command: VBoxManage -q sharedfolder add "boinc_26e350c5e3892277" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\0/shared"
Exit Code: 0
Output:
2026-02-10 18:50:51 (12308):
Command: VBoxManage -q startvm "boinc_26e350c5e3892277" --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_26e350c5e3892277" to power on...
2026-02-10 18:50:51 (12308):
Command: VBoxManage -q snapshot "boinc_26e350c5e3892277" list
Exit Code: -108
Output:
This machine does not have any snapshots
2026-02-10 18:50:52 (12308):
Command: VBoxManage -q bandwidthctl "boinc_26e350c5e3892277" remove "boinc_26e350c5e3892277_net"
Exit Code: 0
Output:
VBoxManage.exe: error: Bandwidth groups cannot be deleted while the VM is running
2026-02-10 18:50:52 (12308):
Command: VBoxManage -q unregistervm "boinc_26e350c5e3892277" --delete
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot unregister the machine 'boinc_26e350c5e3892277' 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
2026-02-10 18:50:53 (12308):
Command: VBoxManage -q unregistervm "boinc_26e350c5e3892277" --delete
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
2026-02-10 18:50:58 (12308): called boinc_finish(-2147467259)
</stderr_txt>
]]>
©2026 CERN