Archived from groups: microsoft.public.windowsxp.hardware (More info?)
You already have the answer. "Exit any application using the port."
Fax program open?
Enable comport sharing in modem setup (I think).
If drivers are messed up - remove modem from device manager, restart PC and
let Windows reload drivers automatically.
> When logging onto the internet: error message "The
> communication port is invalid or busy."
> Query Modem: The port is currently open by another
> location. Exit any application using the port.
> My modem (Conexant HSFiV92 MiniPCI)is on COM 3