: This stops you from viewing the file. You may need specialized decryption software or recovery tools like SwifDoo PDF to attempt to crack the encryption.
: Use sites like Smallpdf or Syncfusion to upload the file, enter the password once, and download an unprotected version. If You Do Not Have the Password
: This restricts printing or editing. You can often bypass this by "Printing to PDF." Open the file in a browser (like Chrome), click Print , and select Save as PDF as the destination.