Buzz
A secured PDF file enforces copyright protection by blocking users from reproducing or distributing its contents. The file's owner or creator sets a password to restrict access, printing, text copying, and editing. If you need to copy text or edit a secured PDF but lack the owner’s password, follow these steps to unlock the file.
Steps
Start
Open the PDF file. If a password is required to open the file, you'll need to use decryption software. This method is CPU-intensive, and even a simple password can take several days to crack, rendering your computer unable to perform any other tasks during the process. For highly encrypted files, the software may not be able to break the encryption at all.
Check the security settings.
Adobe Acrobat (As the file owner)
Open the secured PDF file. You can use Adobe Acrobat for this task. However, you need to be the file's creator or have the password to use this method.
Click on the Security button.
Modify the encryption settings.
Google Drive
Open Google Drive. You will need a free Google account to access Drive. First, adjust the settings to ensure files are converted correctly. In the top right corner, click on the gear icon to open the Settings menu. Under 'Upload settings,' select 'Convert text from uploaded PDF and image files.'
Upload the PDF file.
PDFUnlock
Visit the website. Use your browser to go to www.pdfunlock.com. This site will unlock small PDF files under 5MB for free. This method is only effective for PDFs restricted by the file owner.
Download the file.
Download the converted file. After uploading your file, PDFUnlock will send you the converted version. Save it to any folder on your computer. You can identify the file by the word 'unlocked' in its name.
Check access permissions.
Foxit Reader and CutePDF
Download the latest versions of Foxit Reader and CutePDF Writer.
Use Foxit Reader to open the secured PDF file.
Open a new file. You can check the security settings by clicking on File, then Properties. The security settings will be detailed under the Security tab.
Microsoft XPS Viewer
Open the PDF file using Adobe Reader. Select File, then choose Print. In the list of connected printers, select Microsoft XPS Document Writer. This will convert the PDF to XPS format. When preparing to print, you will be prompted to save the file.
Open the XPS file using XPS Viewer. This program is pre-installed in Windows. In the Tools menu, select Print. Choose PDF Printer from the list. You will need Adobe Acrobat or another PDF editing software like CutePDF.
Save the file.
Ghost Script and Ghost View
Download and install, depending on your operating system, Ghostscript, Ghostview, and GSview from the website http://pages.cs.wisc.edu/~ghost/ or mirrors.
Change the file extension from .pdf to .ps (post-script file).
Open the .ps file and select File -> Convert -> Device (choose pdfwrite), set the resolution (choose 600dpi), then click OK. Save the file in a folder with the .pdf extension.
You can change the extension from .ps to .pdf if necessary. This step is optional.
PDF XChange Viewer
This method is only useful if you know the password.
Go to the File menu, then select Document Properties, followed by Security.
Change the Password Security setting to 'No Security' to remove the protection.
Save the file. Task completed.
Google Chrome
Open Chrome. Press ctrl+O, navigate to the PDF file location, and open it in Chrome.
Right-click on the file. Select Print.
Choose 'Save as PDF'. Save the file at your desired location, such as the desktop.
Mở tập tin vừa được tạo bằng bất cứ phần mềm đọc PDF nào. Tập tin sẽ được mở mà không cần mật khẩu.
SysTools PDF
Tải phần mềm PDF Unlocker. Đây là bản mẫu dùng thử, bạn cần trả phí nếu muốn tiếp tục sử dụng phần mềm này.
Truy cập tập tin PDF bị hạn chế.
Chọn tập tin PDF sau đó nhấp chuột vào nút “Mở” (Open).
Chọn đích đến.
Sau đó nhấp chuột vào nút Mở khóa (Unlock). Với vai trò là người dùng, bạn có thể mở khóa thành công toàn bộ tập tin PDF.
thepdf.com
Mở trình duyệt web và truy cập địa chỉ http://www.thepdf.com/unlock-pdf.html.
Nhấp chuột vào nút "Chọn" (Select) và chọn tập tin PDF từ máy tính.
Click the 'Unlock' button, and the website will upload the file and begin the decryption process.
Take a Screenshot
Advice
- If you're attempting to modify a PDF file you created but lost the password or simply had bad luck, you can resort to password recovery software — for a fee. You can find such software by searching for 'PDF password recovery' on a search engine.
