This can be for several reasons. Two different cases are to be considered:

1 You have only one Network interface on your machine
2 You have several Network interfaces on your machine.

1 - If you have configured only one network interface on your machine, it is likely you have configured an incorrect IP address in the "Network Addresses" form.

If you have checked that the IP address is correctly configured, packed and compiled, and still cannot run the machine as an IOServer, this may be because you have configured address forwarding. An easy to check this is to search for a [AddressForwarding] section in your citect.ini file. You can search the help file for further information about these new ini parameters in v7.

2- If you have multiple network interfaces on your machine, you need to make sure that the one you want to use in Citect comes first when you run a "ipconfig" command line. If the relevant IP address does not come first, the computer setup wizard will not let you run yoru project as an IOServer.

To swap the order of your network connections, please go to Control Panel>Network Connections. The list returned by "ipconfig" is sorted by date - latest enabled, which means that whichever connection was first enabled comes first.

You will therefore need to disable/re-enable all network connections listed there BUT the one you want to use in Citect. This will ensure that the "Citect" network connection will be the oldest, and therefore the first one in the list returned by ipconfig.

Please also read Article Q4732 for more information.