SHA1.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like SHA1.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like ActivePerl-5.28.1.0000-MSWin32-x64-432e1938.exe - to follow. These files were created so that multiple programs (eg. ActivePerl) could share the same SHA1.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 SHA1.dll is attempted to be loaded either when ActivePerl is starting up, or in some cases already running. Some of the most common SHA1.dll errors include:
- Access Violation at address - SHA1.dll.
- SHA1.dll could not be found.
- Cannot find C:\Perl64\site\lib\auto\Digest\SHA1\SHA1.dll.
- Cannot register SHA1.dll.
- Cannot start ActivePerl. A required component is missing: SHA1.dll. Please install ActivePerl again.
- Failed to load SHA1.dll.
- The application has failed to start because SHA1.dll was not found.
- The file SHA1.dll is missing or corrupt.
- This application failed to start because SHA1.dll was not found. Re-installing the application may fix this problem.
Your SHA1.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with ActivePerl), or deleted by a malware infection. Furthermore, SHA1.dll file corruption could be caused from a power outage when loading ActivePerl, system crash while loading SHA1.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.