Email Address Validation

Email addresses imported as Contacts are validated following the RFC822: Standard for ARPA Internet Text Messages.  An email address is validated in parts:

• Email: the whole email address
• LocalPart: the first part of the email address, before the at '@' character, also often known as the Mailbox or Mailbox Name.
• Domain: the second part of the email address, after the at '@' character, consisting of two Labels separated by a period '.'

Email Validation

• Must be composed of both a LocalPart and Domain
• The at '@' character must be between LocalPart and Domain
• Must have only one at '@' character
• May contain more than one period '.'
• Cannot begin or end with period '.'
• Cannot have more than one period '.' consecutively 

LocalPart Validation

• Does not require any period '.'
• Must contain at least 1 character
• May not contain more than 64 characters
• Valid characters are:

• !"#$%&'*+-/0123456789=?.
• @ABCDEFGHIJKLMNOPQRSTUVWXYZ^_
• `abcdefghijklmnopqrstuvwxyz{|}~

• Invalid characters are:

• ()>@,;:\"[]

Domain Validation

• Requires at least 1 period '.' to separate the two Labels, which are both required
• Must contain at least 3 characters, including period
• May not contain more than 255 characters
• Each Label must contain from 1 to 63 characters
• Valid characters are:

• -012345678.
• ABCDEFGHIJKLMNOPQRSTUVWXYZ
• abcdefghijklmnopqrstuvwxyz