As you will probably already be aware if you use the LogicBoxes system from their email notices and announcements, on 10th March 2011 they are turning off their old API URLs. This applies to all the LogicBoxes related modules in WHMCS, which include:

- ResellerClub/DirectI
- NetEartOne
- Stargate (UK2)

In WHMCS we made the necessary changes for this deprecation of the urls well in advance and so if you are using the most recent release of WHMCS (V4.4) then you are already using the new urls.

If however you are running on Version 4.3 or earlier then you will need to upgrade in order to keep those modules working - help & assistance on doing that can be found in our docs @ https://docs.whmcs.com/Upgrading

Additional Step: IP Restrictions Coming In
As part of ResellerClub's general ongoing API improvements, they are also introducing IP restricted access to the API like many other registrars do. This does however mean that you will need to allow your server's IP in the Settings > API section of your account with them for uninterupted service. You can find the IP your WHMCS install is located on that you need to allow there by going to Help > License Information within WHMCS and copying the "Valid IP" value.