I don´t know what version of Freelancer you´re using but IONCROSS only works with the north american version...so that´s probably why you´re getting an error message.
when you have no us version download the trial from the official Freelancer homepage. install it in a differnt folder and copy the "serverresources.dll" from the EXE folder to your fullversion EXE folder. Then Ioncross works fine.
