Hii my name is Luna Falon i am from the technical team if you are facing a problem then you can visit our site.  HP Fax Error Code 346 occurs during fax transmission due to communication issues between the sender and recipient's fax machines. The error indicates that the remote fax machine failed to respond to the initial handshake, leading to the transmission failure. Several factors can cause this problem, including poor line quality, noisy phone lines, or interference during fax transmission. Additionally, incorrect fax settings, incompatible fax protocols, or issues with the recipient's fax machine can also trigger Error Code 346.