Regex patterns used for validating email addresses

This table documents what REGEX patterns are used to perform the email address validation options EMailValidation described in FieldMappings.

Option	REGEX pattern
QUICK	`^(.+)(@)(.+)\.(.+)$`
STRICT	^(?("")(""[^""]+?""@)\|(([0-9a-z]((\.(?!\.))\|[-!#\$%&'\\+/=\?\^`\{\}\\|~\w]))(?<=[0-9a-z])@))(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])\|(([0-9a-z][-\w][0-9a-z]\.)+[a-z0-9]{2,17}))$
RFC822	`(?:(?:\r\n)?[ \t])(?:(?:(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))\<(?:(?:\r\n)?[ \t])(?:@(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))(?:,@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))):(?:(?:\r\n)?[ \t]))?(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\>(?:(?:\r\n)?[ \t]))\|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])):(?:(?:\r\n)?[ \t])(?:(?:(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))\<(?:(?:\r\n)?[ \t])(?:@(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))(?:,@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))):(?:(?:\r\n)?[ \t]))?(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\>(?:(?:\r\n)?[ \t]))(?:,\s(?:(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))\<(?:(?:\r\n)?[ \t])(?:@(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))(?:,@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))):(?:(?:\r\n)?[ \t]))?(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|"(?:[^\"\r\\]\|\\.\|(?:(?:\r\n)?[ \t]))"(?:(?:\r\n)?[` `\t])))@(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t]))(?:\.(?:(?:\r\n)?[ \t])(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[` `\t])+\|\Z\|(?=[\["()<>@,;:\\".\[\]]))\|\[([^\[\]\r\\]\|\\.)\](?:(?:\r\n)?[` `\t])))\>(?:(?:\r\n)?[\t]))))?;\s)`

In case you want to use your own custom REGEX search pattern to validate email addresses, please keep in mind that

the pattern must be stored in a file named EMailValidationRegex.txt,
this file must be a plain text file,
this file must be stored in the same location as the DirSyncConfig.xml file,
this file must not contain any other information but the REGEX pattern to be used.