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Power-cycle the terminal
Disconnect and reconnect the phone cable from the terminal and the phone/line port.
Make sure Check that the phone cord is plugged into the correct port on the terminal. (Line Port)
Confirm Check if the phone line has a dial tone with no pauses or beeps beforehand.
Check if long distance works by calling our auth numbers (18002281257 & 18772664012) on their the line.
Confirm they're Check that the terminal is not on the same line . If they are, call their cell phone or call them back after every step.Confirm if terminal is on a or as the phone.
Check whether or not the terminal is sharing the line with splitter another device/phone via a splitter.
If so, try to remove it and connect the terminal directly to the phone jack.
The phone cable may have a short, try a different physical phone cable.
If they say they do not have another phone cord, ask them to use the cord from their cable is unavailable, try using the cable from the telephone.
Try a different wall jack, if available.
Confirm if they are using the phone line connection is on an Analog or Digital Line . (see 'Analog vs VOIP/Digital' section below)
Software Troubleshooting
Check that the correct comm type is set.
If you are getting connect errors, the terminal might not 'hear' the dial tone, try disabling dial tone check (see below).
Confirm if the merchant needs a dial prefix or pause.
Check Terminal Comm settings:
Try changing the baud rate (see below)
Check that the appropriate auth numbers are set on the terminal (Contact Support for assistance)
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Analog vs VOIP/Digital
A digital phone line may cause the terminal to lose data during transmission. Digital phone systems do not have retry/error correction capabilities, and if a piece of data is lost in transmission, there is no way to recover it. This ends in a failed connection. The longer the connection time, the more likely that a failure will occur. That’s why transactions may go through OK (the connection time is very short) and settlements or downloads may fail (connection time is much longer).
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