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Why a User Cannot Highlight Text in PDF Files? Learn Best Ways Here!

Published By Nilesh Kumar
Debasish Pramanik
Approved By Debasish Pramanik
Published On October 25th, 2023
Reading Time 6 Minutes Reading
Category Adobe PDF

Are you one of the users who is having issues with Adobe Reader’s highlighting? Don’t worry; we’ve got a solid solution that will help you quickly fix the “cannot highlight text in PDF” issue. To highlight the text data in PDF files read the article and explore different solutions to resolve it.

Table of Contents:

User Query:

PDF is the ideal file format for sharing a document across several devices without losing file quality is a PDF file. Additionally, it offers the ability to quickly search for, choose, and highlight certain words. This makes it easier to find the required or important data across large PDF files.

However, In non-editable PDF files, the highlight text function is disabled. Hence at this point, the user can’t highlight any text in the secured PDF files. Let’s see what can be some other reasons:

Reason: Why the Users cannot Highlight Text in PDF?

  • Security Restrictions: Some PDF files have security settings enabled which is used to restrict users to make any changes to the files. The owner can simply enable this to secure files and maintain file integrity.
  • Scanned or Image-based PDFs: In the case of scanned pages or images, users cannot select or highlight the text data. Highlighting requires the presence of editable text in the document.
  • Outdated PDF Reader: Using an outdated version of the PDF reader software may result in compatibility issues, preventing the highlighting functionality from working properly. Updating to the latest version of the PDF reader is recommended.
  • Incompatible PDF Reader: Some PDF readers may not support text highlighting or may have limited annotation features. Using a PDF reader that lacks these capabilities will prevent users from highlighting text.

Other than these, they can be multiple other reasons like Corrupted PDF File, Complex Formatting or Layering, User Error, Insufficient Permissions

Read More: Use Best Way to Convert Non Copyable PDF to Copyable PDF

Using Adobe Reader DC For Enabling Highlight Function?

  1. Initially, open your PDF file in Adobe Acrobat Reader DC.
  2. Then select the option to “Highlight Text tool” from the menu. Selecting it will activate the highlight text tool.
  3. Now navigate to the text that needs to be highlighted.
  4. Simply double-click the highlighted region or right-click the highlighted text to add any additional notes.
  5. After writing the text, simply click the Post button. Open Pop-up Note
  6. Save this altered PDF file wherever you want to.

For Mac Users:

  1. Start your system’s Preview application. It is the programme that Mac OS uses by default to read PDF files.
  2. Select Open from the drop-down menu that appears when you click the File tab.
  3. Next, use the Preview programme and open the PDF file produced by the utility.
  4. A marker icon is plainly visible in the toolbar. Click on the down arrow and choose a new colour to change the highlight tool’s colour too.
  5. Next, choose the tool and select the text that you wish to be highlighted.
  6. After that, save the updated PDF file by selecting File >> Save.

Using An Effective Method to Resolve Cannot Highlight Text in PDF Issue

Sometimes it gets a little difficult to use the above-mentioned for multiple PDF files. So to fix the problem of the highlight text in multiple PDF files it is better to use PDF Password Remover Software and enable highlighting in PDF. This tool simply removes restrictions and unprotect multiple PDF files and lets users perform any action on those files. You can use it to highlight text in any PDF document, even one that has encryption. Apart from this, users can also use this ability to copy, print, edit, comment, and add signatures to PDF files easily.

You won’t have to worry about how to enable highlighting in PDF issues ever again because this application removes PDF security without a password.

Read More: How to Export Data from PDF File

Guided Procedure to Select & Highlight the Text in PDF Files

  • Download the offline software, then use the software’s Add Files or Add Folder buttons to insert files and enable PDF highlighting.

  • Select the Destination Path to save the PDF file’s source after that.

  • After that, click Unlock to allow text highlighting in PDF documents.

  • The software will eventually show the Completion Message on the screen.


In this write-up, we have discussed all the possible solutions regarding why a user cannot highlight text in PDF files. At times, this issue can seriously affect our productivity. Hence, we have talked about dependable and affordable solutions to fix the issue with the highlight function not working in Adobe Reader DC. Additionally, in case of multiple files users can use the automated software to quickly enable the highlight feature in PDF documents.


Q1: Why am I unable to highlight text in my PDF files?

A1: There can be several reasons for being unable to highlight text in PDF files. Common causes include document restrictions, the PDF being a scanned image, or issues with your PDF reader.

Q2: How can I check if a PDF is restricted from text highlighting?

A2: To check if a PDF is restricted:

  • Open the document in your PDF editor.
  • Right-click on the text and go to Properties.
  • See if Comment is allowed or not in Security tab.
  • “Not Allowed” indicates text highlighting restrictions.

Q3: What is the best way to allow text highlighting in a PDF?

A3: The best way to enable highlight text in PDF is to use a dedicated professional tool.

Q4: Are there online tools that can enable text highlighting in a PDF?

A4: Yes, there are online tools that claim to do so. But it’s recommended to use reputable and secure tools to ensure data privacy and integrity.

Q5: Can I highlight text in a scanned PDF?

A5: Highlighting text in a scanned PDF can be challenging since it’s essentially an image. Users may need to use OCR (Optical Character Recognition) software to convert the scanned text into selectable and highlightable text.


By Nilesh Kumar

As a Chief Technical Writer, I know the technical issues faced by home and professional users. So, I decided to share all my knowledge via this blog. I love to help you with challenges while dealing with technical jargon.