Sign

The Sign function adds a digital signature to a PDF document.

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Properties

Input

The following properties specify the PDF document to be loaded and modified by the operation:

File path

Path to the PDF file.

Authentication type

PDF files can be protected using a password or a certificate. This field indicates which type of authentication to attempt when loading the PDF.

1. None
   The document is unprotected and can be opened immediately.
2. Password
   The document is protected by a password.
3. Certificate
   The document is protected by a certificate.

Password:

Only displayed when Authentication type is ‘Password’.

• Password: Password required to access the PDF file.

Note

Note:
All passwords entered into this function’s properties will be visible in plain text in the Linx solution file and in the compiled .NET assembly.

Certificate

Only displayed when Authentication type is ‘Certificate’.

Certificate source:
Source to load the certificate from:

1. File - Load a certificate from a .pfx file.
2. Store - Load a certificate from the Windows certificate store.

File

Displayed when Certificate source is ‘File’.

• Certificate file path: Path to a .pfx file containing a certificate.
• Certificate file password: Password needed to open the certificate file.

Store

Displayed when Certificate source is ‘Store’.

• Certificate: Certificate in the Windows keystore.

Note

Note:
Certificate protected files are not supported by the “Fill form,” “Sign,” “Add watermark,” and “Concatenate” operations. If you need to use the operations on a certificate-protected document, first remove the certificate protection using the “Change protection” operation. The certificate must include the private key to be able to load the document.

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Misc

• Signed at: Location where the signing took place.
• Reason: Reason for signing the document.
• Lock document after signing: Lock the document to prevent further changes.

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Output

File path

Path of the PDF file to write to.

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Signature

Signature placement

Where to place the signature in the document:

1. No visible signature - Don’t display a visible signature.
2. Form signature field - Insert the signature into an existing signature form field.
3. On page - Place a visible signature on a specific page in the document.

Form signature field

Displayed when Signature placement is ‘Form signature field’.

• Field name: Form field name to place the signature in.
• Background image: Path to an image to use as the background for the signature field. This can be left blank if no background image is needed.

On page

Displayed when Signature placement is ‘On page’.

• Position X (mm): Distance of the left side of the signature from the