metadata_cache.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like metadata_cache.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like mighost.exe - to follow. These files were created so that multiple programs (eg. MySQL Database Server) could share the same metadata_cache.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 metadata_cache.dll is attempted to be loaded either when MySQL Database Server is starting up, or in some cases already running. Some of the most common metadata_cache.dll errors include:
- Access Violation at address - metadata_cache.dll.
- metadata_cache.dll could not be found.
- Cannot find C:\Program Files\MySQL\MySQL Server 8.0\lib\metadata_cache.dll.
- Cannot register metadata_cache.dll.
- Cannot start MySQL Database Server. A required component is missing: metadata_cache.dll. Please install MySQL Database Server again.
- Failed to load metadata_cache.dll.
- The application has failed to start because metadata_cache.dll was not found.
- The file metadata_cache.dll is missing or corrupt.
- This application failed to start because metadata_cache.dll was not found. Re-installing the application may fix this problem.
Your metadata_cache.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with MySQL Database Server), or deleted by a malware infection. Furthermore, metadata_cache.dll file corruption could be caused from a power outage when loading MySQL Database Server, system crash while loading metadata_cache.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.