That code looks fine.
It's basically this:
https://www.example-code.com/dataflex/hash_md4.asp

The documentation for comHashStringEnc does not indicate that you need a particular minimum version of Chilkat.

My next question is:
- did you run regsvr32 to install the ActiveX control?

- did you provide a license key to the control to unlock it?
https://www.example-code.com/dataflex/global_unlock.asp

--
Wil