Find the program (e.g., software or Microsoft Works ).
Many free DLL download sites bundle files with malicious code, trojans, or adware. Replacing a system file with a compromised DLL can give hackers full access to your operating system.
Download the latest, official installer for the software and reinstall it. This will cleanly replace all required DLL files, including bdb.dll . Method 2: Check Your Recycle Bin