Free PDF Recovery: Restore Deleted, Unsaved, and Damaged PDF Files

PDF, short for Portable Document Format, as per Wikipedia, is a file format developed by Adobe with the purpose of presenting documents, complete with text formatting and images. A PDF file maintains all the fonts, formatting, graphics, and colors of any original document, regardless of the software or operating system used to produce it.

It has become one of the most widely utilized formats. However, numerous businesses, organizations, and individual users are unaware of how to recover PDF files when they are accidentally deleted or closed without being saved.

If you're experiencing a similar issue, continue reading to learn how to recover deleted, unsaved, or corrupted PDFs on your own.

注意:如果你已经为丢失的 PDF 创建了备份，恭喜你。你可以在这里停止，从 PDF 备份中恢复丢失的文件。如果没有备份，请继续阅读并找到解决方案。

Part 1: Recover Deleted or Lost PDF Files

Applies to: Restore lost PDF files due to deletion, formatting, RAW drive, or other reasons.

With the widespread use of PDF files, the issue of PDF file loss has become a prominent concern. Even if you take every possible precaution to prevent it, there might come a time when you have to deal with this situation. PDF file recovery is often in high demand.

Here, we've compiled two reliable methods to assist you in recovering a lost PDF:

Undelete PDF from Recycle Bin

大多是时候，当你意外删除了PDF文件或将其拖到回收站时，你可以直接从回收站恢复它：

Step 1. Go to the Recycle Bin. Check if the deleted PDF file is present there.

If you're unsure of the name, search for files with the .pdf extension.

Step 2. Select the PDF file and right-click on it. Choose "Restore" to recover the file.

If you didn't spot the PDF file in the Recycle Bin, don't worry. A reliable free file recovery software will help retrieve your lost file.

Recover Lost PFD Files with Free File Recovery Software

When the recycle bin recovery fails, typically, a reliable and potent file recovery program is the optimal solution.

Data Recovery Wizard tools can effortlessly retrieve deleted, formatted PDF files, and more. Even if you have lost your hard disk drive partition on your PC, this magical recovery program can still restore the PDF file.

Aside from PDF recovery, it also boasts numerous other powerful features:

• Supports all types of file recovery, including Word recovery and Excel recovery, etc.
• Supports basic and dynamic disks, RAID drives.
• Supports FAT32, NTFS, EXT2/EXT3 file systems.
• Supports all Windows Operating Systems (from Windows XP to Windows 10).

It offers effortless and rapid data recovery solutions (in just three steps):

Step 1. Select the location

选择你丢失PDF/PPT/Word/Excel文件的驱动器，然后点击“扫描”。

Step 2. Scan for lost documents

Upon completion of the scanning process, click "Documents" in the left panel. You can locate the desired documents by filtering according to file type. Alternatively, you can directly search for the files by their names. Once you find the document, click "Preview" to verify if it is the one you are looking for.

Step 3. Recover Lost Documents

Select the desired PDF/PPT/Word/Excel/TXT/ZIP documents and click the "Recover" button to save them to a different secure location.

Part 2: Recover Unsaved PDF Files

Applies to: Restore lost or closed PDF files without saving. This translates to: "Applies to: Recover lost or closed PDF files without saving."

Most PDF applications have the functionality to create temporary files. When you're editing a PDF on your computer, the application generates a temporary file to serve as a backup for any unsaved changes.

When a PDF is closed abruptly due to sudden hardware failure, power outage, or an unforeseen application error, there is still hope for recovery.

You can attempt to recover it from a temporary file. Here, we'll use Adobe Reader as an example to demonstrate how to restore an unsaved PDF:

Step 1. Locate the file path of PDF temporary files

Here is the path of Adobe PDF temporary files:

• C:\Users\Tracy\AppData\Local\Adobe\Acrobat\DC
• C:\Users\Tracy\AppData\Roaming\Adobe\Acrobat\DC
• C:\Users\Tracy\AppData\Local\Temp

Step 2. Locate and find temporary files of unsaved PDF.

Note: The extensions of temporary files might not be the same as the original PDF files. They can be saved with different file extensions.

Step 3. Copy the temporary files to another secure location and change the file extensions to .pdf.

Step 4. Open the PDF file in Adobe Reader.

Once that's done, you can open the PDF file again to view and edit it.

If the method provided in this part does not work or Adobe Reader or other PDF editing applications continue to corrupt, proceed to the next section.

You will learn how to fix corrupted PDF files and applications on your own.

Part 3: Repair Corrupted PDF

Applies to: Resolving PDF file corruption, PDF application corruption with error messages, etc.

If you encounter these error messages, your PDF or PDF files are corrupted:

• PDF file cannot be read with your software
• The root object is invalid or absent
• The file is damaged or corrupted
• It contains information not recognized by the viewer
• Format error - Not a PDF file or corrupted

通常，这类错误可归因于软件故障，包括浏览器、邮件程序、操作系统、防病毒软件或防火墙。那么，如何解决PDF文件损坏及其应用的问题呢？请继续阅读，寻找解决方案：

Repair Corrupted PDF Files

Here are two methods you can opt for to repair corrupted PDF files:

1. Recover corrupted PDF from temporary files (as mentioned in Part 2).

2. Utilize a PDF repair tool for assistance

Although tool software currently doesn't offer PDF repair tools, we've compiled a list of recommended online resources that can assist you with this issue.

Hope these tools can fix your PDF:

• Kernel for PDF Repair
• Stellar Repair for PDF
• SysTools PDF Recovery

Note: If these recommended tools also don't work, please contact the Adobe or PDF application producers for assistance.

Repair Corrupted PDF Application

Sometimes, when PDF files become corrupted, it's not because the PDF document itself is damaged but due to an issue with the PDF application.

When the PDF application is corrupted or displays error messages, you can attempt the following solutions to fix the corrupted PDF:

• Download and reinstall the PDF application once more
• Check for updates and install the latest version of Adobe Acrobat/Adobe Reader

Open Adobe Acrobat > Help > Check for Updates...

Utilize third-party services to repair the PDF application.

To fix a corrupted Adobe Acrobat DC or Adobe Reader PDF:

If you are an Adobe Reader user, you can attempt to repair a corrupted Adobe PDF using the following steps:

Step 1. Open Adobe Acrobat Reader DC.

Step 2. Click "Help" from the top menu, and select "Repair Adobe Reader Installation".

If this advice is unhelpful, your best option is to contact Adobe Corporation, the PDF producer, or Adobe Support for assistance.

Bonus Tips for Protecting PDF Files

Aside from understanding how to restore and repair PDF files, it is also essential to learn techniques to protect them from deletion, formatting, or even virus infections.

Here are some additional tips to help you comprehensively safeguard your computer, device, and valuable files, including PDFs:

1. Enable the firewall, run antivirus software, and regularly scan and remove viruses and malware.

It's clear that the best way to prevent viruses and malware from infecting your programs, deleting or encrypting your valuable files, such as PDFs, Word documents, Excel spreadsheets, etc., is essential.

2. Establish a routine backup of PDF files

The other method, although simple, is also very useful for preventing PDF loss. You can manually copy the saved PDF files or utilize a reliable file backup software to create an automatic backup to another device.

Todo Backup provides a 3-step backup mode to assist you in efficiently backing up desired files:

Step 1. Click the "Select backup contents" button to initiate the backup process.

Step 2. There are four data backup categories: File, Disk, OS, and Mail. Click File.

Step 3. Both local and network files will be listed on the left. You can expand the directory to select the files to back up.

Step 4. Follow the on-screen instructions and select the location where you want to save the backup.

Click "Options" to encrypt the backup with a password in "Backup Options", set the backup schedule, and choose to initiate the backup at a specific event in "Backup Scheme". You can also explore various other options to customize the backup task as per your requirements.

Step 5. You can save the backup to your local drive, the tool's cloud service, or a NAS device.

Step 6. Todo Backup allows users to back up data to both third-party cloud drives and its own cloud drive.

If you want to back up data to a third-party cloud drive, select Local Drive, scroll down to add a Cloud Device, then add and log in to your account.

You can also opt for the tool's built-in cloud drive. Click on Tools Cloud, sign up with your Tool Account, and log in.

Step 7. Click "Backup Now" to initiate the backup process. Once the backup task is completed, it will be displayed as a card on the left side of the panel. You can right-click the backup task to manage it further.

3. Install compatible versions of a PDF editor on your computer

Although we recommend installing the latest version of PDF on your computer, we must emphasize that system and software compatibility is equally crucial.