network problem in the virtual box,please help!!

[mohammed510]

I am using ubuntu as the main machine
I made inside the virtual box three machines :
I installed Centos on two of them and windows XP on the third one
My problem is that I need to make anetwork between the three machines and the main machine and the internet
I used INTERNAL NETWORK configurations to make this network and the network successfully made but between the three virtaul computers only without the internet connection
I used HOST INTERFACE configurations to do what I want but when I started the virtual computers there is an error message appeared

Failed to open '/dev/net/tun' for read/write access. Please check the permissions of that node. Either run 'chmod 0666 /dev/net/tun' or change the group of that node and make yourself a member of that group. Make sure that these changes are permanent, especially if you are using udev.
VBox status code: -3100 (VERR_HOSTIF_INIT_FAILED).


Result Code:
NS_ERROR_FAILURE (0x80004005)
Component:
Console
Interface:
IConsole {e3c6d4a1-a935-47ca-b16d-f9e9c496e53e}

I changed the permissions of the file /dev/net/tun by this command
sudo chmod 0666 /dev/net/tun

When I start the virtual computers another error message appeared

Failed to initialize Host Interface Networking.
VBox status code: -3100 (VERR_HOSTIF_INIT_FAILED).


Result Code:
NS_ERROR_FAILURE (0x80004005)
Component:
Console
Interface:
IConsole {e3c6d4a1-a935-47ca-b16d-f9e9c496e53e}

I realy needs this virtual network and I don't know where is the error
Please help !!

[Sasquatch]

Which version of VB are you using? The newer versions, 2.1.x and 2.2.x no longer need virtual interfaces for Host Interface/Bridged networking. You can select the NIC directly. Please download and install 2.1.4 or newer (2.2.0 has a few issues, see the discussion thread for more info).