You say that you have the dip switch settings as per the manual! What are they? Looking at the back of the module, the switch bank on the left side must have all the switches in the up (ON) position and the bank on the right side must all be in the off (DOWN) position, unless this card is installed in the expansion module. In that case, the system will tell you how it wants the switches set. You really need to verify this first. If they are all correct, best bet is to try a known working module because as Wally says, it's either a switch setting issue or a dial tone issue from the carrier.