D3D9Core.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like D3D9Core.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. Movavi Video Converter 2020) could share the same D3D9Core.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 D3D9Core.dll is attempted to be loaded either when Movavi Video Converter 2020 is starting up, or in some cases already running. Some of the most common D3D9Core.dll errors include:
- Access Violation at address - D3D9Core.dll.
- D3D9Core.dll could not be found.
- Cannot find C:\Users\Tester\AppData\Roaming\Movavi Video Converter 20 Premium\D3D9Core.dll.
- Cannot register D3D9Core.dll.
- Cannot start Movavi Video Converter 2020. A required component is missing: D3D9Core.dll. Please install Movavi Video Converter 2020 again.
- Failed to load D3D9Core.dll.
- The application has failed to start because D3D9Core.dll was not found.
- The file D3D9Core.dll is missing or corrupt.
- This application failed to start because D3D9Core.dll was not found. Re-installing the application may fix this problem.
Your D3D9Core.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with Movavi Video Converter 2020), or deleted by a malware infection. Furthermore, D3D9Core.dll file corruption could be caused from a power outage when loading Movavi Video Converter 2020, system crash while loading D3D9Core.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.