I have an imageCLASS MF275dw. The printer reports that it's on the latest firmware.
I'm trying to print from Linux with CUPS and IPP Everywhere. When Country/Region (in Menu -> Management Settings -> Device Management -> Select Country/Region) is set to some locales, such as "Latin America (Other)", "Asia (Other)", and "India (IN)", the IPP naturalLanguage attribute is set incorrectly to `en- ` (the letters 'en', a dash, and two spaces). Other locales set the attribute properly, like Australia and `en-au`.
Per RFC 8011 Section 5.1.9 and RFC 5646, the two spaces after the hyphen are invalid. As a result, printing systems like CUPS reject the printer when using IPP. There seem to be other models affected, as seen in this thread. I tried reaching out to customer support in my region, but they weren't helpful. I hope this gets someone's attention here.
