Hi, I have installed VBOX 3.0.12 on fc12 which is running libvirt-0.7.1. Now when i try to connect using virsh using uri "virsh -c vbox+tcp:///system" this is the error i get: error: internal error unable to initialize VirtualBox driver API error: failed to connect to the hypervisor But it connects successfully with this ur: "virsh -c vbox:///system" i have also qemu installed on the same machine and connects successfully with uri "virsh -c qemu+tcp:///system" Libvirt is listening on tcp port:16509 any idea what am i doing wrong? Here is a detailed message: LIBVIRT_DEBUG=1 virsh -c vbox+tcp:///system 11:10:45.469: debug : virInitialize:279 : register drivers 11:10:45.495: debug : virRegisterDriver:776 : registering Test as driver 0 11:10:45.495: debug : virRegisterNetworkDriver:614 : registering Test as network driver 0 11:10:45.495: debug : virRegisterInterfaceDriver:645 : registering Test as interface driver 0 11:10:45.495: debug : virRegisterStorageDriver:676 : registering Test as storage driver 0 11:10:45.495: debug : virRegisterDeviceMonitor:707 : registering Test as device driver 0 11:10:45.495: debug : virRegisterSecretDriver:738 : registering Test as secret driver 0 11:10:45.496: debug : virRegisterDriver:776 : registering Xen as driver 1 11:10:45.496: debug : virRegisterDriver:776 : registering OPENVZ as driver 2 11:10:45.496: debug : virRegisterDriver:776 : registering PHYP as driver 3 11:10:45.506: debug : vboxRegister:80 : VBoxCGlueInit found API version: 3.0.12 (3000012) 11:10:45.506: debug : vboxRegister:92 : VirtualBox API version: 3.0 11:10:45.506: debug : virRegisterDriver:776 : registering VBOX as driver 4 11:10:45.506: debug : virRegisterNetworkDriver:614 : registering VBOX as network driver 1 11:10:45.506: debug : virRegisterStorageDriver:676 : registering VBOX as storage driver 1 11:10:45.506: debug : virRegisterDriver:776 : registering ESX as driver 5 11:10:45.506: debug : virRegisterDriver:776 : registering remote as driver 6 11:10:45.506: debug : virRegisterNetworkDriver:614 : registering remote as network driver 2 11:10:45.506: debug : virRegisterInterfaceDriver:645 : registering remote as interface driver 1 11:10:45.506: debug : virRegisterStorageDriver:676 : registering remote as storage driver 2 11:10:45.506: debug : virRegisterDeviceMonitor:707 : registering remote as device driver 1 11:10:45.506: debug : virRegisterSecretDriver:738 : registering remote as secret driver 1 11:10:45.506: debug : virConnectOpenAuth:1273 : name=vbox+tcp:///system, auth=0x43d940, flags=0 11:10:45.506: debug : do_open:1042 : name "vbox+tcp:///system" to URI components: scheme vbox+tcp opaque (null) authority (null) server (null) user (null) port 0 path /system 11:10:45.506: debug : do_open:1052 : trying driver 0 (Test) ... 11:10:45.506: debug : do_open:1058 : driver 0 Test returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 1 (Xen) ... 11:10:45.506: debug : do_open:1058 : driver 1 Xen returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 2 (OPENVZ) ... 11:10:45.506: debug : do_open:1058 : driver 2 OPENVZ returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 3 (PHYP) ... 11:10:45.506: debug : do_open:1058 : driver 3 PHYP returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 4 (VBOX) ... 11:10:45.506: debug : do_open:1058 : driver 4 VBOX returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 5 (ESX) ... 11:10:45.506: debug : do_open:1058 : driver 5 ESX returned DECLINED 11:10:45.506: debug : do_open:1052 : trying driver 6 (remote) ... 11:10:45.506: debug : doRemoteOpen:535 : proceeding with name = vbox:///system 11:10:45.508: debug : remoteIO:7421 : Do proc=66 serial=0 length=28 wait=(nil) 11:10:45.508: debug : remoteIO:7483 : We have the buck 66 0xb75df008 0xb75df008 11:10:45.509: debug : remoteIODecodeMessageLength:7032 : Got length, now need 64 total (60 more) 11:10:45.509: debug : remoteIOEventLoop:7347 : Giving up the buck 66 0xb75df008 (nil) 11:10:45.509: debug : remoteIO:7514 : All done with our call 66 (nil) 0xb75df008 11:10:45.509: debug : remoteIO:7421 : Do proc=1 serial=1 length=56 wait=(nil) 11:10:45.509: debug : remoteIO:7483 : We have the buck 1 0x9fb2ea8 0x9fb2ea8 11:10:45.510: debug : remoteIODecodeMessageLength:7032 : Got length, now need 208 total (204 more) 11:10:45.510: debug : remoteIOEventLoop:7347 : Giving up the buck 1 0x9fb2ea8 (nil) 11:10:45.510: debug : remoteIO:7514 : All done with our call 1 (nil) 0x9fb2ea8 11:10:45.510: debug : do_open:1058 : driver 6 remote returned ERROR 11:10:45.510: debug : virUnrefConnect:257 : unref connection 0x9fb0b30 1 11:10:45.510: debug : virReleaseConnect:214 : release connection 0x9fb0b30 error: internal error unable to initialize VirtualBox driver API error: failed to connect to the hypervisor Regards Anuj