Once you download it you are going to have to put it somewhere and that somewhere depends on the program(s) you have installed that are trying to find the file. For example, if it is Advanced System Care (ACS) that is complaining, the file needs to go here
(depending on your version):
C:\Program Files\IObit\Advanced System Care 6
If downloading the file does not help, you need to tell us more information:
The rtl120,bpl file is not a Windows file. A BPL file is a Borland Precompiled
Library file and:
it has nothing to do with XP
The rtl120.bpl file gets installed with some third party programs you may have installed... something like Advanced System Care (ASC), TuneUp Utiliites or AVG (or others). If you do not provide the names of these third party programs you have installed and
do not provide the entire and exact error message as you see it, nobody will be able to help you (unless you get lucky).
Do you now or have you ever had any of those things installed or have you ever used any third party applications on your system where the product description includes such descriptive phrases as:
cleaner, mechanic, detective, doctor, cure, optimize, inspector, clean up, tune up, speed up, fix up, compact, compress, faster, power, boost, booster, eraser, muncher. one click fix, new, intuitive, mistakes, stops crashes, stops errors, improves, saves you
money, risk free, guaranteed or any third party program that has an icon resembling a gear, cog, tool belt, wrench, spanner, screwdriver or swooping arrows?
Here is an example of a useless reply regarding rtl120.bpl marked as the "Most Helpful Reply" from a Microsoft engaged Forum Moderator "expert". One reason it is useless is that the Microsoft engaged Support Engineer "expert" does not seem to know that the
rtl120.bpl is not a Windows system file:
I don't see the other Microsoft engaged Support Engineer "expert" advice to '"use your favorite search engine" to look for the file is going to help you either. I would never download any file from an untrusted source on the Internet.
If you use the Search function in the top of the pages of the MS Answers forums, you will find a few other ideas.
If you have any of those things installed, you may need to uninstall them and reinstall them to replace the missing file or provide more information on exactly what you are seeing, when you are seeing it, if you have any of those products installed and what
you think might have happened to the system since the last time it worked properly.