For many system administrators and also for many users, IP blocks due to Exim Syntax Error are the daily bread. When the user's IP is blocked, their local email client will not work properly as it will not be able to connect to the server. This time we are going to see what causes these Exim Syntax Error crashes and we will also see how we can solve them.
What causes a crash due to Exim Syntax Error?
This problem is generated on the user's side, and often originates when using email clients. The problem occurs when incorrect data is sent from our IP to the mail server, and the most frequent case usually occurs with the recipient's email address.
When we send an email through a local client (such as Outlook, Thunderbird, etc.) sometimes said program adds quotes to the recipient's address ('[email protected]'). This is common when the recipient is not added to our contact list. If we process the sending without removing these quotes, the mail server will take it as a syntax error and could block our IP.
The problem does not only occur with quotes, but also with a series of characters that are not supported. Let's see which ones are valid and which ones are not.
Not valid:
The letter “ñ”
The accents
Characters other than periods or hyphens (example ” $ = %)
Valid:
Spot (.)
Hyphens (- and _)
All numbers (0 to 9)
All letters except ñ (both lowercase and uppercase)
Of course, blocking can also occur if unrecognized characters are sent in the subject of the email or in the body. Basically, any strange data that our mail client sends to the server can cause an Exim Syntax Error crash. In most cases the problem originates when writing the recipient's address, so it is always a good idea to double check it before hitting the send button.
How can I solve that?
When a block of this kind occurs, the quickest way to solve it is to contact the hosting provider so that the IP can be unblocked. Another possible solution is to restart our Internet modem, since if we have a dynamic connection a new IP will be automatically assigned.
Now we know that certain characters are capable of causing a block due to Exim Syntax Error, and the good thing is that we also know what are the methods to make said block no longer bother us.
