Hello mwholderby,
Since there isn't a dial tone when you press the HOOK button, your MF5950dw may require service. I recommend you call our Desktop Printing and Imaging Solutions Group at 1-866-261-9362 or 1-800-OK-CANON (652-2666), Monday - Friday 8:00 a.m. to 8:00 p.m. ET (excluding holidays). The support representative can perform additional troubleshooting steps to try and resolve the issue.
If the issue remains, your service options will be provided. Please be near your unit and have the 8 character serial number from the back of your printer ready at the time of your call.
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