Have you ever thought that what causes an email syntax error? what characters may appear in an email address? In the field of computer and programming languages, an extra white space or dot can ruin a program or operation. There are the same rules in the world of emails. A proper email address must include some common components. An error will appear if each part fails to follow its rules.
Types of errors
There are several different kinds of errors that can occur in a program. It includes syntax errors, runtime errors, and logical errors. Here we will talk about syntax errors.
Syntax
An email address is formatted as local-part & domain. The local part can be up to 64 octets long and the domain can be up to 255 octets long. RFC 5322 (parts 3.2.3 and 3.4.1) and RFC 5321 include formal definitions, with a more understandable form provided in the informational RFC 3696[b] and associated errata.
An email address may also contain a display name for the receiver that comes before the address specification, which is now surrounded by angled brackets, for example, John Smith john.smith@example.org
Local Part
The local element of the email address is left unquoted or surrounded by quotation marks.
If unquoted, it may use any of these ASCII characters:
- uppercase and lowercase Latin letters A to Z and a to z
- digits 0to 9
- printable characters !#$%&’*+-/=?^_`{|}~
- dot ., provided that it is not the first or last character and provided also that it does not appear consecutively (e.g., Doe@example.comis not allowed)
The maximum overall length of an email address’s local part is 64 octets.
- space and special characters “(),:;<>@[\]are allowed with restrictions (they are only allowed inside a quoted string, as described in the paragraph below, and in that quoted string, any backslash or double-quote must be preceded once by a backslash);
- comments are allowed with parentheses at either end of the local part; e.g., smith(comment)@example.com and (comment)john.smith@example.com are both equivalent to john.smith@example.com.
Because it is case-insensitive, the local component should be sent to the domain email administrator. All other local parts are case-sensitive, so jsmith@example.com and JSmith@example.com designate different mailboxes; however, many businesses consider uppercase and lowercase letters to be comparable.
Despite the large range of special characters that are technically acceptable, organizations, mail services, mail servers, and mail clients do not always accept them all.
It is common practice to avoid using certain special characters, to avoid email rejections.
Domain
The domain name portion of an email address must adhere to rigorous guidelines. It must fulfill the requirements for a hostname, a set of dot-separated DNS labels, each label limited to 63 characters in length. It should consist of;
- uppercase and lowercase Latin letters A to Z and a to z;
- digits 0to 9, provided that top-level domain names are not all-numeric;
- hyphen -, provided that it is not the first or last character.
The LDH rule is the name given to this rule (letters, digits, hyphens). Furthermore, the domain can be an IP address literally enclosed in square brackets [], such as jsmith@[192.168.2.1] or jsmith@[IPv6:2001:db8::1].
Comments are allowed in the domain as well as in the local part; for example, john.smith@(comment)example.com and john.smith@example.com(comment) is equivalent to john.smith@example.com
Reserved Domain
RFC 2606 states that certain domains, such as those meant for documentation and testing, should not be resolvable, and that mail addressed to mailboxes in them and their subdomains should be non-deliverable as a result. For Example, invalid, example.com, example.net, and example.org are notable e-mail domains.
Syntax Error
The term ‘syntax’ refers to the programming language’s grammar. Each language has its own set of rules for how commands can be written in that language, which is known as language syntax.
Syntax errors are malformed or incomplete email addresses that won’t be included in your audience. If you encounter a syntax error when attempting to send your message, it is most likely due to incorrect personalization fields or URL addresses in your message content – either the subject, body HTML or Plain Text version.
When a programmer produces an inaccurate line of code, a syntax error occurs. The majority of syntax problems are caused by missing punctuation or a misspelled name. If a syntax error occurs in a compiled or interpreted computer language, the code will fail.
Recognizing and comprehending common syntax problems can help you code more efficiently and confidently.
Causes of Email Syntax Error
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Missing/Unmatched Parentheses
For many programming languages, parentheses are an important kind of punctuation. It aids in the organization of code, the implementation of strings, and the execution of functions. When a beginner starts developing code, it is easy for them to forget how many parentheses they have used or if they are appropriately lined up.
The code will not be compiled if one end of the parenthesis is missing. Furthermore, if the parenthesis is not properly aligned, the code may perform the function improperly.
How to repair It: If there is a syntax mistake, double-check that the parenthesis is properly matched. If one end is missing or incorrectly aligned, enter the repair and check that the code can be compiled.
It also helps to keep the code as orderly as possible. If the parenthesis is lined up or plainly visible, a developer can keep track of them and avoid errors far more easily.
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Undeclared/Misspelled Variables
Variables are used to store the value of numbers, text, or data. Variables give coders flexibility and allow them to use programming languages more efficiently. A variable must be declared early in the code for it to function. Inexperienced programmers may forget to declare a variable or misspell it anywhere in their code.
How to fix it: Make certain that the variable is declared in the code. If the variable is not declared, enter a line of code that declares it before using it.
If you are certain that you did declare it, review the code for any spelling issues or changes. The code will not function properly if something is misspelled or modified.
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Unmatched/Missing Quotes
In strings, quotations are used to display a statement. To display the statement, double quotations (“) or single quotes (‘) can be used inside parentheses. They cannot be used alternately. Some coders may fail to add the end of a quote or use mismatched quotes, resulting in an error.
How to Repair It: Check to see if a quote is missing. Check the quotations in the same way you would check the parenthesis. If the quotations are misaligned, repair the problem and run the code to ensure it works.
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Incomplete/Misspelled Return Statements
Return statements instruct the software to do a previous action. There may be a return statement or return value included in the code. A return statement may contain one of the previously stated problems — undeclared variable, missing parenthesis, or typo.
How to Fix It: Check the return statement for spelling and punctuation problems.
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Missing Semicolon
Semicolons are useful in many programming languages because they signal a break in a line of code. Semi-colons are more commonly used in C and Java. Coders who use these languages are more likely to encounter this syntax error. When a semicolon is absent from a line of code, the statement continues until the next semicolon is encountered. If there is another punctuation or statement, it will usually be flagged as an error.
How to Repair It: Check the statement’s end to determine if a semicolon is missing. When creating code, get into the habit of putting a semi-colon at the end of each sentence, just like you would a period.
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Incorrect URLs
Incorrectly inserted URLs may also result in syntax problems. Examine any links you included in the message to ensure their format is correct. Keep an eye out for typos, spaces, or other characters that could cause the URL to break.
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Using images from the Files and images
Syntax issues may also arise if you embed an image’s URL in the message rather than adding it through the Files and pictures menu. Check your images again, then remove the ones you inserted and replace them with Files and images.
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Missing Information
Something could be missing from an address. For example, john@aol lacks “.com,” but john@aolcom lacks the dot. Retry the missing information.
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The email address has extra space
An address might have extra spaces before, after, or even in the midst of it because of the way some export utilities operate. A syntax error may be reported because of these extra spaces, or an otherwise legitimate address. To remove spaces from text, use Excel’s TRIM function, or look for a similar option in the help documentation of your preferred spreadsheet application.
- The contact’s email address contains typos.
A syntax error may also occur if the contact’s email address contains typos. For example, “joe@gamil.com” or “jane@yhoo.com” will be blocked because Gmail and Yahoo were misspelled. Fix the typos and try again.
Examples
Valid Email addresses
- simple@example.com
- common@example.com
- style.email.with+symbol@example.com
- email-with-hyphen@example.com
- fully-qualified-domain@example.com
- name+tag+sorting@example.com(may go to user.name@example.cominbox depending on the mail server)
- x@example.com(one-letter local-part)
- example-indeed@strange-example.com
- test/test@test.com(slashes are a printable character, and allowed)
Invalid Email addresses
- example.com(no @ character)
- A@b@c@example.com(only one @ is allowed outside quotation marks)
- a”b(c)d,e:f;g<h>i[j\k]l@example.com(none of the special characters in this local-part are allowed outside quotation marks)
- just”not”right@example.com(quoted strings must be dot separated or the only element making up the local part)
- this is”not\allowed@example.com(spaces, quotes, and backslashes may only exist when within quoted strings and preceded by a backslash)
- this\ still\”not\\allowed@example.com(even if escaped (preceded by a backslash), spaces, quotes, and backslashes must still be contained by quotes)
Why is it Important to Fix Syntax Errors?
Even if the syntax error is minor, the code will not be compiled. As a result, the developer won’t know if their software is working, hence addressing syntax problems as soon as possible is essential.
Syntax problems might be annoying, but they are simple to correct. As a coder acquires experience, he or she is less likely to make grammatical errors and builds confidence in their coding talents.
Email Syntax Error Checker
In real-time, the email syntax validator checks and identifies email ids that do not adhere to well-known email syntax rules. In email lists, email syntax errors are the most common. They should be removed from the list. The email syntax checker API validates syntax at the point of entry, preventing invalid email ids from entering the system in the first place.
Email syntax checker verifies and checks for the following email address components.
The Local Part
- Uppercase and lowercase. Latin letters A-Z and a-z.
- Digits from 0 to 9
- A dot (.) unless it is the first or last character or quoted. Also, unless quoted, it does not appear consecutively. For instance, mark..russell@example.com is not permitted, but “mark. Russell”@example.com is.
- Space and “(),:;>@[] characters are permitted with limitations. They are only permitted within a quoted string. A backslash or double quote must be preceded by a backslash.
- Parentheses are allowed at the end of the local component for comments. Mark.Russell(comment)@server.com and (comment)mark.russell@server.com, for example, are both equal to mark.russell@server.com.
The @ symbol
- Presence of @ symbol after the local part and before the domain name.
- Single presence of @ symbol.
Second level Domain
A domain name is a string of letters and numbers. It refers to an Internet space. It is controlled and maintained by a single mailbox provider or company. The domain name should contain the following characters:
Latin lowercase and uppercase letters A-Z and a-z
- Numbers ranging from 0 to 9.
- hyphenation: –
- IP address in square brackets: mark.russell@[192.168.2.1] or mark.russell@[IPv6:2001:db8::1].
- In the case of a subdomain, a dot is chosen. For instance, mark.russell@subdomain.example.com
Top-level Domain
The right-most label expresses the top-level domain; for example, the domain name www.kleanmail.com is part of the top-level domain com.
Here are the five most common domain extensions to consider:
- .com
- .net
- .org
- .co
- .us
Email syntax validation is critical for preserving an online reputation and cleansing the email list.