Portable Document Format (PDF) files are one of the most ubiquitous file types today. Created by Adobe in the early 1990s, PDFs revolutionized document sharing by providing a standardized format that could preserve source formatting regardless of application software, operating system, or hardware platform.
Decades later, PDFs remain incredibly popular for distributing documents that need to look exactly the same when opened on any device. But like any file, PDFs can become corrupted, damaged, or even lost. When that happens, you need PDF recovery tools and techniques to get those files back.
This comprehensive guide will teach you everything you need to know about recovering lost, unsaved, corrupted, and deleted PDF files on both Windows and Mac operating systems.
Why PDF Files Can Become Inaccessible
Before we dive into the recovery process, let’s look at some common reasons PDF files can become inaccessible:
- Accidental deletion – It’s easy to permanently delete a PDF simply by pressing the delete key or emptying the recycle bin/trash.
- Corruption or damage – PDF files may become corrupted if there are errors in the file data itself. This is often due to improper downloading, unexpected program crashes, or file system errors.
- Unsaved changes – If your computer crashes or loses power before you save changes to a PDF, the unsaved changes will be lost.
- Formatting drives – Formatting a drive or partition will permanently delete all files, including PDFs.
- Hardware failure – Physical damage to a hard drive or storage device can make data recovery necessary.
- Malware or viruses – Malicious programs may damage, alter, or delete PDF files.
- Lost devices – If a USB drive, external hard drive, or other device with PDF files on it becomes lost or stolen, those PDFs could be gone for good.
The bottom line is PDF files face many of the same risks as any other digital document. But not to worry – with the right tools, recovering lost or damaged PDFs is possible in most cases.
Method 1: Recover Unsaved or Lost PDF Files
If your PDF file never got saved or you lost your changes before saving, there may still be a way to get that document back. Here’s how:
Use Auto-Recovery in Adobe Acrobat
Adobe Acrobat and Adobe Reader have an auto-save feature that saves temporary copies of open PDFs at regular intervals. This protects against data loss from crashes, power failures, or forced shutdowns.
To recover an unsaved PDF using auto-recovery:
- Open Adobe Acrobat/Reader
- Navigate to File > Open
- Browse to the auto-save folder location:
- Windows: C:\Users\%USERNAME%\AppData\Roaming\Adobe\Acrobat\Autosave
- Mac: /Users/USERNAME/Library/Preferences/Adobe/Acrobat/DC/Autosave
- Look for a file with the
.adobesaveextension and open it. This should contain your unsaved changes!
- Use File > Save As to save the recovered file as a PDF.
Note: Autosaved files are deleted when you close the program, so act quickly!
Check Temporary Files
Many applications save temporary versions of open documents, which get deleted when you close the program. For PDFs opened in Acrobat/Reader, check this folder:
- Windows: C:\Users\%USERNAME%\AppData\Local\Adobe\Acrobat\DC\Reader\Recent
- Mac: /Users/USERNAME/Library/Preferences/Adobe/Acrobat/DC/Reader/Recent
Temporary files may have cryptic names, but look for the
Use File Recovery Software
If auto-save or temp files don’t help, your last resort is file recovery software. Recoverit is an excellent choice that works for both Windows and Mac. It can scour your hard drive to find residual traces of lost or unsaved PDF files, Word documents and more.
Follow these steps:
- Download and install Recoverit
- Select the drive partition you were working in when the PDF was lost
- Click “Start” to scan the drive
- Preview found PDF files and select those you want to recover
- Choose a new storage location to save the recovered PDFs
By digging deep at the file system level, Recoverit can often retrieve even permanently deleted files. Just be sure to avoid saving recovered files to the same drive you scanning to prevent data overwriting.
Method 2: Repair a Corrupted PDF
If your PDF file has become corrupted or damaged, there are several ways you can attempt to repair it:
Update or Reinstall Adobe Acrobat/Reader
Issues with the PDF viewer software itself can sometimes cause errors. Updating to the newest version of Acrobat/Reader may resolve problems opening damaged PDFs.
You can also try reinstalling the application entirely. On Windows, use the built-in cleaner tool first to fully uninstall before reinstalling.
Open PDF in Web Browser
Modern web browsers have built-in PDF viewers that you can use to open files. Try opening the corrupted PDF in your browser (Chrome, Firefox, Edge, Safari, etc.) to see if that can render the file properly.
Use PDF Repair Software
For more serious corruption, Stellar Repair for PDF is an excellent tool available for Windows and Mac. It uses advanced algorithms to scan damaged PDF files, identify errors, and repair the corruption.
Follow these simple steps:
- Download and install Stellar Repair for PDF
- Add the corrupted PDF file
- Click “Repair” and wait for analysis
- Preview the file after repairing to check the results
- Save the repaired PDF
Stellar Repair for PDF can fix PDFs with a wide range of damage – from simple rendering issues to complete file corruption. It’s the best option when basic troubleshooting fails.
Method 3: Recover Deleted or Lost PDF Files
Accidentally deleting a PDF or having files become lost due to hardware failure or other data loss requires recovery tools tailored for that purpose. Here are two options that work great:
Restore from Recycle Bin or Trash
If you just deleted a PDF recently, the fastest solution is to restore it from the recycle bin (Windows) or trash (Mac).
- Windows: Open the recycle bin, right-click the PDF and choose
- Mac: Open the trash, right-click the PDF and choose
This allows you to easily recover deleted files if the recycle bin/trash hasn’t been emptied yet.
Use Recoverit File Recovery Software
For PDFs deleted long ago or not found in the recycle bin/trash, you need advanced file recovery. Once again, Recoverit is the best solution available. It can recover deleted files even if you permanently deleted them or formatted the drive entirely.
To recover deleted PDFs with Recoverit:
- Select the drive partition the PDFs were stored on
- Scan the drive to identify recoverable deleted files
- Filter results to show only PDFs
- Preview found PDFs and choose those to recover
- Save the recovered PDF files to a safe location
Recoverit digs deep to find residual data from deleted files. As long as the storage space hasn’t been overwritten, recovery success rates are excellent.
Important: Avoid saving recovered data to the same drive you are scanning, as this can overwrite deleted file traces. Always save to external storage instead.
Tips to Avoid Losing PDF Files
They say that an ounce of prevention is worth a pound of cure. While the recovery methods above work great, it’s always better to avoid data loss in the first place. Here are some handy tips:
- Create backups – Regularly back up important PDF files to external drives or cloud storage. This gives you copies to restore from if needed.
- Enable autosave – Turn on auto-recovery in your PDF reader to capture unsaved changes.
- Safely eject drives – Use the “Eject” option before disconnecting external drives to avoid corruption.
- Update software – Keep PDF readers, operating systems, and security software up-to-date. Updates fix bugs and vulnerabilities.
- Use anti-virus tools – Protect your system against malware that could damage PDF files.
- Handle drives carefully – Don’t bump or drop external hard drives that contain PDFs.
- Store PDFs across multiple locations – Don’t keep your only copy of a PDF in a single place. Losing that one drive means losing the file forever.
Following best practices like these reduces the chances of disasters happening down the road. But if you do need to recover a PDF, refer back to the techniques in this guide!
Key Takeaways on PDF Recovery
To summarize, here are the key points to remember:
- PDF files can become inaccessible due to deletion, corruption, or loss. But specialized tools make PDF recovery possible in most cases.
- For unsaved PDF files, first check the auto-recovery files and temp folders in your PDF reader app. If that fails, use Recoverit file recovery software.
- To repair corrupted PDFs, try updating your PDF reader, opening in a browser, or using a dedicated PDF repair tool like Stellar Repair for PDF.
- Recover deleted PDFs quickly by restoring from the recycle bin/trash whenever possible. For deeper recovery, use Recoverit file recovery software.
- Make frequent backups and follow other best practices to avoid losing PDF files in the first place. But recovery tools should cover you if anything does go wrong.
As you can see, with the right knowledge and software tools, no PDF loss scenario needs to be permanent. Arm yourself with this PDF recovery guide and you’ll always have a way to get lost files back.
Besides, here are the best ways to convert ACSM to PDF for your reference.
FAQs About PDF Recovery
Here are answers to some frequently asked questions about recovering lost, corrupted, and deleted PDF files:
Can you recover unsaved or lost PDF documents?
Yes, by using the auto-recovery files and temp folders in your PDF application, or file recovery software like Recoverit, you can often recover unsaved PDFs. Act quickly before the temp files get deleted.
Is it possible to repair a corrupted PDF file?
Yes, try updating your PDF reader, opening the file in a browser, or using dedicated repair software like Stellar Repair. This can fix many types of PDF corruption.
How do I recover a permanently deleted PDF?
Use powerful file recovery software like Recoverit to scan your hard drive and resurrect deleted PDFs. Avoid overwriting the storage space during the recovery process for best results.
Where are deleted PDF files stored before permanent erasure?
On Windows, recently deleted files go to the recycle bin. On Mac, they go to the trash. Restore PDFs from here if possible. After permanent deletion, traces remain on the hard drive until overwritten.
Can you recover PDFs after formatting a hard drive?
Yes, formatting only deletes file system data, not the contents themselves. File recovery software can restore PDFs and other files after formatting or partitioning drives.
Is it better to use software or professional services for PDF recovery?
Top software like Recoverit and Stellar Repair can recover most lost or damaged PDFs for a one-time cost. Hardware problems may require professional data recovery, but try DIY software solutions first.
How can I avoid needing to recover PDF files in the future?
Make frequent backups, enable autosave features, safely eject drives, install anti-virus protection, keep software updated, and handle drives carefully. Follow best practices to avoid data loss.
Can PDFs be recovered after a system crash or hardware failure?
Yes. As long as the drive is physically intact, file recovery software can restore PDFs lost due to OS crashes, power outages, controller failures, and other hardware issues.
Is it safe to recover PDFs and save them to the same drive?
No, always save recovered files to a different drive. Saving back to the same drive you are scanning can overwrite deleted file traces that the software needs to recover your data.