I have a couple numbers i am unable to digitally fax to. I can put a printed doc into the scanner, select fax, enter the number and it will send the fax just fine. If I select the PDF, print to fax, put in the number and click send it always comes back with a status of "Failed - Recipient connection lost" and gives an error code of 358, Most often, 321, less often, and 388, least often. It is only to two particular numbers, other fax numbers within the same organization and same building even will work as well.
Try turning off the error correction mode in the fax settings and try a slower fax speed.
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Tried it, I've set the speed to Fast, Medium, and Slow. Tried all of those with ECM on and off. Had the recipient double check that their fax was clear of jams, and had paper. I've tried sending just a single page, and tried the same page with a cover sheet. I've reduced image quality. I'm out of options. It's like when trying to send digitally these numbers disconnect before my machine starts sending. But like I said I can throw the pages on the machine, dial the number on the touch pad hit send and it goes no problem. 🤯 Lost at this point.
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