update_sync.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like update_sync.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. ZoneAlarm Pro Antivirus+Firewall 2019) could share the same update_sync.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 update_sync.dll is attempted to be loaded either when ZoneAlarm Pro Antivirus+Firewall 2019 is starting up, or in some cases already running. Some of the most common update_sync.dll errors include:
- Access Violation at address - update_sync.dll.
- update_sync.dll could not be found.
- Cannot find C:\Program Files (x86)\CheckPoint\ZoneAlarm\avsys\update_sync.dll.
- Cannot register update_sync.dll.
- Cannot start ZoneAlarm Pro Antivirus+Firewall 2019. A required component is missing: update_sync.dll. Please install ZoneAlarm Pro Antivirus+Firewall 2019 again.
- Failed to load update_sync.dll.
- The application has failed to start because update_sync.dll was not found.
- The file update_sync.dll is missing or corrupt.
- This application failed to start because update_sync.dll was not found. Re-installing the application may fix this problem.
Your update_sync.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with ZoneAlarm Pro Antivirus+Firewall 2019), or deleted by a malware infection. Furthermore, update_sync.dll file corruption could be caused from a power outage when loading ZoneAlarm Pro Antivirus+Firewall 2019, system crash while loading update_sync.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.