The Linux Modem How-To
18.3"You are already online! Hang up first." (from minicom)
The modem has its CD signal on. Either you are actually online (a remote modem is sending you a carrier) or your modem has been setup to always send the CD signal. In minicom, type at&v to see if &C or &C0 is set. If so, CD will be on even if you are offline and you'll erroneously get this error message. The fix is to set &C1 in the init string or save it in the modem.
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