PDF File Extension

PDF file icon
Portable Document Format
  • Developer
    Adobe Systems
  • Popularity
    3.5 (33 votes)

What is PDF file?

Files with the .PDF extension contains text or graphic documents, stored in a format designed in order to provide portability between applications and platforms. It stores a flat document of constant appearance, a digital printout. Specification was developed in the 90s by the Adobe company. It is based on the PostScript language. Since 2008 it is an open format, defined in ISO 32000 – previously it was a proprietary file format.

Current implementation enables to place within a document:

  • Text and fonts,
  • Vector graphic and raster images,
  • Annotations,
  • Forms,
  • Layers,
  • 3D objects,
  • Multimedia (including video content)

PDF file can be encrypted and signed digitally, and it may include metadata and attachments. It is a synthesis of the PostScript programming language, font nesting system, and structural storing of data within a single file, compressed if necessary.

The technology behind PDF files

In the process of creating PDF files, these 3 technologies are utilised:

  1. PostScript – in order to generate content, graphic and layout
  2. System embedding fonts used within a document – enables to change them and transfer along with the documents
  3. Structural mass memory system – enables to merge all elements and any additional content into a single file, utilising data compression if necessary.

Programs which support PDF file extension

The list that follows enumerates programs compatible with PDF files, divided into 6 categories based on operating system on which they are available. Files with PDF suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

How to open file with PDF extension?

There can be multiple causes why you have problems with opening PDF files on given system. On the bright side, the most encountered issues pertaining to Portable Document Format files aren’t complex. In most cases they can be addressed swiftly and effectively without assistance from a specialist. We have prepared a listing of which will help you resolve your problems with PDF files.

Step 1. Download and install Adobe Reader

The most common reason for such problems is the lack of proper applications that supports PDF files installed on the system. This issue can be addressed by downloading and installing Adobe Reader or different compatible program, such as Adobe Acrobat, Foxit Reader, Sumatra PDF. On the top of the page a list that contains all programs grouped based on operating systems supported can be found. If you want to download Adobe Reader installer in the most secured manner, we suggest you visit Adobe Systems Incorporated website and download from their official repositories.

Step 2. Update Adobe Reader to the latest version

If you already have Adobe Reader installed on your systems and PDF files are still not opened properly, check if you have the latest version of the software. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. This can be one of the causes why PDF files are not compatible with Adobe Reader. The most recent version of Adobe Reader is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Set the default application to open PDF files to Adobe Reader

If you have the latest version of Adobe Reader installed and the problem persists, select it as the default program to be used to manage PDF on your device. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Selecting the first-choice application in Windows

  • Clicking the PDF with right mouse button will bring a menu from which you should select the Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the Adobe Reader installation folder. Confirm by checking Always use this app to open PDF files box and clicking OK button.

Selecting the first-choice application in Mac OS

  • Right-click the PDF file and select Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • Select the appropriate software and save your settings by clicking Change all
  • If you followed the previous steps a message should appear: This change will be applied to all files with PDF extension. Next, click the Continue button to finalize the process.

Step 4. Verify that the PDF is not faulty

Should the problem still occur after following steps 1-3, check if the PDF file is valid. It is probable that the file is corrupted and thus cannot be accessed.

1. The PDF may be infected with malware – make sure to scan it with an antivirus tool.

Should it happed that the PDF is infected with a virus, this may be that cause that prevents you from accessing it. It is advised to scan the system for viruses and malware as soon as possible or use an online antivirus scanner. PDF file is infected with malware? Follow the steps suggested by your antivirus software.

2. Ensure the file with PDF extension is complete and error-free

If the PDF file was sent to you by someone else, ask this person to resend the file to you. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. It could happen the the download process of file with PDF extension was interrupted and the file data is defective. Download the file again from the same source.

3. Check if the user that you are logged as has administrative privileges.

Some files require elevated access rights to open them. Log out of your current account and log in to an account with sufficient access privileges. Then open the Portable Document Format file.

4. Make sure that the system has sufficient resources to run Adobe Reader

The operating systems may note enough free resources to run the application that support PDF files. Close all running programs and try opening the PDF file.

5. Ensure that you have the latest drivers and system updates and patches installed

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with Portable Document Format file. It may be the case that the PDF files work properly with updated software that addresses some system bugs.

Conversion of a PDF file

File Conversions from PDF extension to a different format
File conversions from other format to PDF file
Do you want to help?

If you have additional information about the PDF file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on PDF file.

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