Have installed 5610A on a Win XP single machine, using both WinFax Basic 10.02 and WinFaxPro 10.02, both of which are supposed to be XP compatible. I was assured by 3Com tech support before purchase that the modem does support distinctive ring and is XP compatible. I cannot get any software to recognize that the modem supports distinctive ring, although the XP software itself does show it as supporting it when queried. I have tried to upgrade the modem firmware itself to V 92 from the WebSite, but the upgrade software itself is not designed for XP, and the communication software that came with the modem does not function under XP. Can you help, or is there any software available which will allow me to run this modem under XP and use distinctive ring?