How to Fix Adobe Acrobat Error: PDF Is Already Open or In Use
Question details
Users are unable to open specific PDF documents and receive an error message indicating that the file is locked or currently being used by another application.
- Product
- Adobe Acrobat / Adobe Acrobat Reader DC
- Device & OS
- not provided
- Scenario
- Attempting to open a PDF that is very large, stored on a shared network drive, or freshly generated by a third-party application.
- Observed behavior
- Adobe Reader blocks the document from opening and displays the error prompt: "There was an error opening this document. This file is already open or in use by another application."
Ensure that no other background applications, such as your email client's preview pane or the software that generated the PDF, are actively selecting or processing the file.
Copy the PDF to Your Local Computer
Moving the file from a shared network drive to your local storage bypasses network latency and shared-access locking issues.
Network drives and shared folders often employ file-locking mechanisms to prevent multiple users from editing a document simultaneously. If a synchronization delay occurs, Adobe Acrobat may falsely detect the file as being in use.
Click 'OK' or close the Adobe error message currently on your screen to dismiss the dialogue box.
Open your File Explorer (Windows) or Finder (Mac) and navigate to the shared drive or network folder where the problematic PDF is stored.
Right-click the PDF file, select 'Copy', and then navigate to a local directory such as your Desktop or Documents folder to 'Paste' it.
Double-click the newly copied file on your local drive. It should now open seamlessly in Adobe Acrobat without triggering the network locking error.
Update Adobe Acrobat and Restart
Installing the latest version of Acrobat resolves known bugs and file-handling glitches introduced in previous updates.
Open Your PDF Files Instantly with WPS Office
If Adobe Acrobat continues to lock your files with false error prompts, try using WPS Office. Its built-in, lightweight PDF reader allows you to seamlessly open, view, and edit PDF documents without the frustrating network-locking errors.
- 1. Download WPS Office: Visit the official WPS website to download and install the free version of WPS Office.
- 2. Locate your PDF: Find the PDF file that is returning the 'already in use' error in your file browser.
- 3. Open with WPS PDF: Right-click the document, select 'Open with', and choose WPS Office from the list of applications.
- 4. View your document: Instantly access and read your PDF document without any file-locking interruptions.
Frequently Asked Questions
Why does Adobe Acrobat think my PDF is open when it isn't?
This typically happens when background processes, such as the File Explorer preview pane, network syncing tools, or the application that originally generated the PDF, fail to release the file handle properly after interacting with it.
Can a buggy software update cause the 'PDF is already in use' error?
Yes. Certain releases of Adobe Acrobat Reader DC have contained bugs affecting how the software handles file locking, particularly for generated files. Updating to the latest version via Help > Check for Updates generally resolves these specific bugs.
How do I force close a PDF file that is stuck in use?
The easiest way is to restart your computer, which clears all active file handles. Alternatively, you can open the Task Manager (Ctrl+Shift+Esc on Windows) and force quit any running instances of Adobe Acrobat or the software used to generate the PDF.
