What is the failure to send the VAT electronic invoice to the mailbox?

Cause analysis of failure in sending VAT electronic invoice to mailbox 1. The other server timed out. The other party's mail server is not turned on for some reason or the system has a serious failure. In this case, you can usually wait a few hours before sending it, or send it to another mailbox of the other party. 2. The email address is wrong. Because e-mail addresses are composed of various characters, it is easy to misread English, numbers and other characters or make mistakes on the computer if you are not careful. You can check the case of the e-mail address. 3. The sent file does not conform to the specifications. Whether the invoice file we sent has been compressed in the folder and meets the size requirements can be sent to the other party's mailbox normally.