leptonlib.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like leptonlib.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like 1-2-3PDFConverter.exe - to follow. These files were created so that multiple programs (eg. 123 PDF Converter) could share the same leptonlib.dll file, saving valuable memory allocation, therefore making your computer run more efficiently.
Unfortunately, what makes DLL files so convenient and efficient, also makes them extremely vulnerable to problems. If something happens to a shared DLL file, either it goes missing or gets corrupted in some way, it can generate a "runtime" error message. Runtime is pretty self-explanatory; it means that these errors are triggered when leptonlib.dll is attempted to be loaded either when 123 PDF Converter is starting up, or in some cases already running. Some of the most common leptonlib.dll errors include:
- Access Violation at address - leptonlib.dll.
- leptonlib.dll could not be found.
- Cannot find C:\ProgramData\PCOCRTemp\leptonlib.dll.
- Cannot register leptonlib.dll.
- Cannot start 123 PDF Converter. A required component is missing: leptonlib.dll. Please install 123 PDF Converter again.
- Failed to load leptonlib.dll.
- The application has failed to start because leptonlib.dll was not found.
- The file leptonlib.dll is missing or corrupt.
- This application failed to start because leptonlib.dll was not found. Re-installing the application may fix this problem.
Your leptonlib.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with 123 PDF Converter), or deleted by a malware infection. Furthermore, leptonlib.dll file corruption could be caused from a power outage when loading 123 PDF Converter, system crash while loading leptonlib.dll, bad sectors on your storage media (usually your primary hard drive), or quite commonly, a malware infection. Thus, it's critical to make sure your anti-virus is kept up-to-date and scanning regularly.