Why is ESS Allegro not functioning?

Windows has detected a missing file that ESS Allegro needs to opperate properly. I am able to hear sounds still, but I would still like to replace the missing file. Allthough
I do not understand the purpose of the file,
or how I’m still able to hear audio without it, Windows has identified it as………..
“C:\WINDOWS\system32\drivers\es198x.sys”.
Will any kind soul who understands what this file is for,or who might be able to direct me towards a solution, please show me the way. The real mystery to me is how did the file come up missing in the first place?
Is there a website where I can find this file in order to download and reinstall or repair the driver?