libidn.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like libidn.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like MpSigStub.exe - to follow. These files were created so that multiple programs (eg. Nitro Pro) could share the same libidn.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 libidn.dll is attempted to be loaded either when Nitro Pro is starting up, or in some cases already running. Some of the most common libidn.dll errors include:
- Access Violation at address - libidn.dll.
- libidn.dll could not be found.
- Cannot find C:\Program Files\Nitro\Pro\13\libidn.dll.
- Cannot register libidn.dll.
- Cannot start Nitro Pro. A required component is missing: libidn.dll. Please install Nitro Pro again.
- Failed to load libidn.dll.
- The application has failed to start because libidn.dll was not found.
- The file libidn.dll is missing or corrupt.
- This application failed to start because libidn.dll was not found. Re-installing the application may fix this problem.
Your libidn.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with Nitro Pro), or deleted by a malware infection. Furthermore, libidn.dll file corruption could be caused from a power outage when loading Nitro Pro, system crash while loading libidn.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.