We have just changed ISP

Question

We have just changed ISP from Demon to BTHomeHUB including a change from the previous modem/router (an SMC wireless ADSL Barricade g) to a British Telecom (BT) wireless modem/router. Maybe it's not relevant but the latter is connected via ethernet to a Del PC and we are able to run our 3 Mac laptops, via WiFi, very efficiently with this set up. Having earlier downloaded the relevant drivers to our Macs (but not to the PC which would not allow the download for some reason) our Lexmark Z1480 wireless printer was working fine with the previous WiFi set up with the Macs (which is all that we require) but the printer is now apparently not communicating with the new BT modem/router (orange flashing WiFi icon on the printer which needs to be continuous green.The Del PC will still not allow the Lexmark download but anyway this was not necessary to have our Macs printing wirelessly on the earlier set up.With thanks in advance for any assistance you can offerDelwin Clifford