How to Fix EFS or File-in-Use Errors When Signing PDFs
Question details
The user encounters EFS (Encrypting File System) or file-in-use errors while trying to apply a digital signature to a PDF, which often clears form fields and forces the application to restart.
- Product
- Adobe Acrobat
- Device & OS
- Windows
- Scenario
- Applying a digital signature to a PDF form or document.
- Observed behavior
- An error message appears stating the file is in use or an EFS error occurs. This blocks the signature, clears filled form fields, and usually requires restarting the software to proceed.
Ensure your PDF document is saved directly to a local drive (like your Desktop or Documents folder) rather than a network drive or a cloud-synced folder, as network syncing can temporarily lock the file.
Resolve File Locking and Background Processes
Clear out stuck background processes, disable the Windows Explorer preview pane, and move the file to local storage to prevent access conflicts during the signing process.
File-in-use errors typically happen when another background process, syncing tool, or even the Windows file previewer accesses the PDF at the exact moment Acrobat tries to save the signature.
Press Ctrl + Shift + Esc to open the Task Manager. Locate any Adobe Acrobat processes, right-click them, and select 'End task'.
Open File Explorer. Click on the 'View' tab at the top and ensure the 'Preview pane' button is deselected so it is turned off.
If the file is on a network drive or a OneDrive/Dropbox synced folder, copy the file to a local, unsynced directory like your Windows Desktop.
Open the locally saved PDF, fill in any required fields, and attempt to apply your digital signature again.
Update or Repair Adobe Acrobat
Fix underlying software bugs or corrupt installation files that cause Acrobat to crash or mismanage file permissions during signing.
Sign PDFs Smoothly with WPS PDF
Avoid frustrating file-in-use errors and clunky signature workflows. WPS Office provides a robust, built-in PDF editor that makes adding digital signatures and filling forms quick, secure, and completely error-free.
- 1. Open your PDF: Launch WPS Office and open the PDF document you need to sign.
- 2. Navigate to Fill & Sign: Click on the 'Protect' or 'Fill & Sign' tab located on the top navigation ribbon.
- 3. Create your signature: Click on 'Sign' to draw, type, or insert an image of your signature.
- 4. Apply and Save: Drag and drop the signature onto the appropriate line in the document, then click the 'Save' icon.
Frequently Asked Questions
Why does Adobe Acrobat say the file is in use when I try to sign?
This typically occurs if the Windows Explorer preview pane is actively displaying the file, a background Acrobat process has frozen, or the PDF is saved on a network or cloud-sync drive that is currently reading the file.
What is an EFS error in PDF signing?
EFS (Encrypting File System) errors during PDF signing usually happen due to permission conflicts, outdated software bugs, or endpoint security software incorrectly blocking access to the temporary files Acrobat creates while signing.
Will repairing Acrobat fix the issue of form fields clearing out?
Yes, repairing the installation can fix corrupted program files that cause unexpected behavior like clearing data. However, ensuring both Acrobat and your Windows OS are updated to their latest versions is the most effective fix.
How do I turn off the Preview pane in Windows to stop file locking?
Open File Explorer, click the 'View' tab at the top of the window, and click 'Preview pane' so that it is no longer highlighted. This simple step often frees up locked PDF files immediately.
