The most feature-filled fax sending method. Allows full control over all aspects of fax transmission.

Formal Definition


Name Type Comments
Username String As provided during registration
Password String As provided during registration
FaxNumbers String A single fax number or a list of semicolon-separated fax numbers, e.g: 1-212-3456789;+44161-9998888;01132-45 45 45 45. Maximum number of recipients: see the System Limitations page. If multiple fax numbers are provided, multiple transactions will be created. All such transactions will share a single ParentTransactionID, whose value is the TransactionID of the FIRST transaction in the batch.This property also accepts named lists from the control panel’s list management section, in the form list={name} where {name} is the literal name from the list management screen.
Contacts String Semicolon-delimited list of names. The entered string will appear: (1) for reference in the outbound queue, and (2) in the outbound fax header. When faxing to a list managed online through your account, this field will be populated by the “Person Name” field in the list, or if unavailable, by the “Company Name” field in the list. Individual recipients and lists may be mixed.
FilesData base64Binary

Binary data of the document(s). If two or more documents are uploaded, concatenate their binary data.The total length of this parameter is the sum of all items in the FileSizes parameter.

If an uploaded file’s size is greater than 250KB, or if experiencing timeouts, consider using the Chunk Data Upload methods. If referencing a file uploaded by these methods (using its SessionID in parameter FileSizes below), this parameter is ignored. Send a zero-size buffer.

Note: Your development environment may automatically pick up this property’s data type and implicitly encode it in base64 without you needing to do so explicitly. For example, PHP5 does this.

FileTypes String List of FileType, semicolon-separated, e.g:TXT;DOC;HTML;HTML.
The number of items in this list should match the number of documents, even if all documents are of the same type. Can be any one of the file types supported by InterFAX. (If TXT, the character set is taken from control panel setting Preferences -> Outgoing -> Default text charset encoding.)
FileSizes String List of numbers, semicolon-separated, each defining the length of a document (before base64-encoding).Example: 12034;8888;18478
If the file(s) were uploaded with the Chunk Data Upload method, add the string /sessionID=[session ID]. The SessionID is the one returned by the StartFileUpload call.
Example: 12034;8888;18478/sessionID=123456
Postpone DateTime Time to schedule the transmission. In case no scheduling is required (i.e. ASAP), use any date in the past, like '2001-12-31T00:00:00-00:00'.
RetriesToPerform Integer Number of transmission attempts to perform, in case of fax transmission failure. The minimum interval between two subsequent attempts is set through your account defaults.
CSID String Sender CSID (up to 20 characters). If not provided, user’s default CSID is used.
PageHeader String The fax header text to insert at the top of the page. Enter a string template to send a fax with a dynamically-populated header. For placeholder documentation, see your online settings under Preferences -> Outgoing -> Header Properties. For example, in the string To: {To} From: {From} Pages: {TotalPages} the placeholders {To}, {From}, and {Pages} will be populated by their respective values.Alternatively, enter Y or a null string to send the fax with a constant header that is defined in your online preferences above or N to send the fax without a header.
JobID String Reserved for future use
Subject String Up to 60 characters, to be used as a reference only. The Subject parameter can be obtained by status query, but is not included in the transmitted fax message.
ReplyAddress String One or more optional, semicolon-delimited e-mail addresses to which feedback messages will be sent. If null, the user’s default reply address (from the online control panel) is used.
PageSize String A4LetterLegal, or B4. If not provided, user’s default page size is used. Add -fit to fit (enlarge or reduce) an image file to a certain page size, e.g. A4-fit.
PageOrientation String Portrait or Landscape. If not provided, user’s default page orientation is used.
IsHighResolution Boolean True ==> Fine, False ==> Standard. True renders documents more finely but takes longer to transmit (may therefore be more costly).
IsFineRendering Boolean True ==> Optimize for greyscale, False ==> Optimize for B&W. “False” is recommended for textual, black & white documents, while “True” is better for greyscale text and for images.


Name Type Comments
SendfaxEx_2Result Long In case of successful submission – the value contains a Transaction ID.
In case of a failure, a negative value is returned. List of return codes is shown on Appendix A.