Such an error is clear - it does not mean that the file is missing, but that the program cannot access it
There can be many reasons, they can be solved:
- by simply reinstalling the program
- by registering that dll file (regsvr32 command)
- by moving/copying it to the system (Windows/System32 or ...) or some other folder
- and if everything is fine, it may happen that the antivirus blocks access. Add it to the exceptions list.
And whatever you do, make sure you have admin privileges