DLL Files Fixer requires to function because it writes files to C:\Windows\System32 and modifies the Registry. If you run a cracked version, you are giving administrative rights to unknown code. Hackers frequently hide keyloggers, ransomware, or botnet clients inside these "portable" executables.
It is a staple for "PC repair" USB sticks alongside other diagnostic tools. How to Use It Safely dllfiles fixer 33913080 portable dll top