i am trying to call the component

component implements="IStringsFactory" {

the implements is in the same folder as component

interface {
    public ILocalizedStrings function getStrings(required string directory, required string defaultLocale);
}

i am getting an error

Could not find the ColdFusion component or interface com.IStringsFactory.

There is some information you are not giving us here. The code you include says your CFC is implementing

IStringFactory

, but the error is talking about

com.IStringFactory

. Those are two different things, and you don't show us where that

com.StringFactory

reference comes from.

It works in all versions except 2021 And even I created a mapping to fix it but still errors out

Right, good to know. But back to what I said...

I removed it and added a mapping it does connect mappings either

Can't make any sensible comment about "I created a mapping", "I removed the mapping" without any knowledge of what the file system structure is, or what the mapping values were etc. As for not working on CF2021 and working elsewhere... it's likely a server config issue (if this code works at all anywhere else), so it probs more a case of it not working on that CF2021 server instance, rather than "it's something with CF2021". Still: I'd not be worrying about other ppl's work interfering with this, and I'd be sticking to yer own work and where it's wrong for now. Assume Lucee / CF / etc all work correctly is configured correctly, and it's your code or config that's off. That will help focus your efforts.