player.dat is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like player.dat, 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. Speed MP3 Downloader) could share the same player.dat 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 DAT 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 player.dat is attempted to be loaded either when Speed MP3 Downloader is starting up, or in some cases already running. Some of the most common player.dat errors include:
- Access Violation at address - player.dat.
- player.dat could not be found.
- Cannot find C:\Program Files (x86)\SpeedMP3Downloader\res\player.dat.
- Cannot register player.dat.
- Cannot start Speed MP3 Downloader. A required component is missing: player.dat. Please install Speed MP3 Downloader again.
- Failed to load player.dat.
- The application has failed to start because player.dat was not found.
- The file player.dat is missing or corrupt.
- This application failed to start because player.dat was not found. Re-installing the application may fix this problem.
Your player.dat file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with Speed MP3 Downloader), or deleted by a malware infection. Furthermore, player.dat file corruption could be caused from a power outage when loading Speed MP3 Downloader, system crash while loading player.dat, 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.