Here's the story: After I installed my Lexmark X85 multifunction device, I tried to dial up my usual ISP with DUN and got a 633 error - com port in use. It was working perfectly before. I tried to dial up with Hyperterminal - it worked fine - and the modem diagnostics worked fine - normal responses. I then uninstalled the Lexmark drivers and tried to remove all the references to fax and fax services on my PC, as I have heard that these can cause a 633 error as they listen for incoming calls. Still no joy. I then went into Task Manager and stripped all the processes down to the bare system processes - I heard that usually if a fax program is listening for calls, it will be in the process list. Still error 633. Tried reinstalling modem drivers and using them from a different source. It is a MiniPCI Conexant 56k. I would be SO grateful for help. Jonathan

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