Other PDF Issues

Fix PDF Signature Disappearing When Emailed from Acrobat on iPhone

Rana Garcia Oct 19, 2026 869 views

Question details

The user is experiencing an issue where a signature added to a PDF document fails to display when the file is sent via email.

How to Fix PDF Signatures Disappearing When Emailed from Acrobat on iPhone

Product: Adobe Acrobat Reader
Device & OS: iPhone (iOS)
Scenario: Signing a PDF document on an iPhone and then sharing it as an email attachment.
Observed behavior: The emailed PDF arrives with the standard content completely intact, but the added name and signature are entirely missing from the document.

Before you start

Ensure your iPhone has a stable internet connection so you can access the App Store, and verify that you remember your Apple ID password in case an app update is required.

Solution 1Recommended

Update Adobe Acrobat Reader to the Latest Version

Installing the latest app update resolves a known software bug that prevented signatures from being properly embedded during email sharing.

The issue of signatures disappearing was identified as a bug in older versions of Adobe Acrobat Reader for iOS (specifically around versions 18.09.13). The developers released a permanent fix in version 18.12.00. Updating your application ensures the signature is properly integrated into the file before sharing.

Open the App Store

Navigate to your iPhone's home screen and tap the App Store icon.

Search for Adobe Acrobat

Tap the Search icon at the bottom of the screen and type 'Adobe Acrobat Reader' into the search bar.

Update the Application

Locate the app in the search results and tap the 'Update' button next to it. If the button says 'Open', you are already on the latest version.

Update Adobe Acrobat Reader to the Latest Version

Update Successful: Once updated to version 18.12.00 or later, your newly signed PDFs will retain their signatures when shared via email.

Solution 2

Create and Share a Flattened Copy Manually

If you cannot update your app immediately, manually creating a flattened copy merges the signature into the document permanently so it cannot disappear.

Sign and Share PDFs with WPS Office

Reliably Sign and Share PDFs Using WPS Office

Avoid frustrating signature loss bugs by using WPS Office to sign and share your PDF documents. WPS securely flattens your digital signatures, ensuring they remain perfectly visible on any device your recipient uses.

1. Open PDF in WPS Office: Launch the WPS Office mobile app and open the PDF document you need to sign.
2. Add Your Signature: Tap 'Tools' at the bottom, select the 'PDF Annotation' or 'Fill & Sign' feature, and place your signature on the document.
3. Save and Share: Tap the 'Share' icon. WPS Office will automatically ensure the document and its signature are properly formatted for emailing without data loss.

Free, lightweight, and incredibly fast mobile PDF editorFully compatible with standard PDF formats and Adobe Acrobat filesEasily draw, type, or insert image-based signatures on your mobile deviceSeamless and reliable sharing via email or direct link from within the app

microsoft office alternative - wps office

Frequently Asked Questions

What does flattening a PDF mean?

Flattening a PDF merges all interactive elements, such as digital signatures, annotations, and fillable form fields, into the main visual layer of the document. This makes the elements permanent and prevents them from disappearing or being edited when opened on different devices or software.

Why do PDF signatures sometimes disappear when sent from an iPhone?

This usually occurs due to software bugs or compatibility issues in the PDF reader app. If the app fails to properly embed or 'flatten' the signature layer before attaching the file to an email, the recipient's software may only read the underlying blank document layer.

Can I recover a signature that disappeared from an emailed PDF?

No, once the PDF is sent and received without the signature layer, the recipient cannot recover it from that specific file. You will need to re-sign the original document on your device, ensure it is flattened or updated, and resend it.

Does WPS Office properly flatten PDF signatures for email?

Yes, WPS Office handles PDF annotations and signatures securely. When you sign a document and share it via email using WPS Office, the signature is reliably embedded, ensuring the recipient sees exactly what you signed.

PDF Troubleshooting