We have installed McAfee virus protection and I can no longer FTP in Scala.

It may be that your network administrator choose to block the FTP inbound and outbound ports in McAfee. You can either turn this feature off or exclude InfoChannel 3 from the port block.

To change this setting got to McAfee's VirusScan Console, select Access Protection, and under 'Ports to Block' you will see 'Prevent FTP Inbound' and 'Prevent FTP Outbound'. You can simple turn these off by unchecking them, or you can select each one and choose edit. In the edit window under 'Excluded Processes' enter MMOS.exe to allow InfoChannel 3 to use these FTP ports.