Qt5Gui_Ad_5_9.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like Qt5Gui_Ad_5_9.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like Setup.exe - to follow. These files were created so that multiple programs (eg. AutoCAD) could share the same Qt5Gui_Ad_5_9.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 Qt5Gui_Ad_5_9.dll is attempted to be loaded either when AutoCAD is starting up, or in some cases already running. Some of the most common Qt5Gui_Ad_5_9.dll errors include:
- Access Violation at address - Qt5Gui_Ad_5_9.dll.
- Qt5Gui_Ad_5_9.dll could not be found.
- Cannot find C:\Program Files\Autodesk\Autodesk AdSSO\Qt5Gui_Ad_5_9.dll.
- Cannot register Qt5Gui_Ad_5_9.dll.
- Cannot start AutoCAD. A required component is missing: Qt5Gui_Ad_5_9.dll. Please install AutoCAD again.
- Failed to load Qt5Gui_Ad_5_9.dll.
- The application has failed to start because Qt5Gui_Ad_5_9.dll was not found.
- The file Qt5Gui_Ad_5_9.dll is missing or corrupt.
- This application failed to start because Qt5Gui_Ad_5_9.dll was not found. Re-installing the application may fix this problem.
Your Qt5Gui_Ad_5_9.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with AutoCAD), or deleted by a malware infection. Furthermore, Qt5Gui_Ad_5_9.dll file corruption could be caused from a power outage when loading AutoCAD, system crash while loading Qt5Gui_Ad_5_9.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.