Deleting localization files on your machine is typically fine, but as you’ve seen sometimes applications don’t like it.
Just make sure to back up first (which is what I advise everyone to do before making any deletion that you’re not 100% certain of). Once you do that, if you delete those files and they stay away, great.
But keeping those files off your machine? That’s not necessarily so easy. I’ll explain why.
Become a Patron of Ask Leo! and go ad-free!
Windows and its translations
As you probably already know, Windows supports multiple languages. You’ll find it in the local language of many different countries around the world.
That doesn’t necessarily mean that an application (like iTunes, for example) would appear in those language as well. You may have to adjust iTunes settings to display the application in another language. While Windows does support common techniques for doing so, many software companies choose to develop their own international or localized support, particularly if the application they’re providing is also available on platforms other than Windows.
As a result there’s some inconsistency in the way that applications support multiple languages. That’s why you may see multiple language files for different programs. That’s also why some files stay deleted and some applications might automatically reinstall those files if they notice that they’re missing.
How do I remove redundant language files?
You won’t find a general-purpose utility to handle this for you. If a program like iTunes automatically replaces the missing languages, I don’t know of a workaround. The same is true for just about any other application that decides that its language files are important.
My best recommendation is to make sure that you always use the custom or advanced installation when you install a program on your machine. If they’re going to be present, any options for installing (or not installing) the various languages available are probably in the setup.
If the setting is not there, then I really don’t know of an official, comprehensive way to remove these files.
But I have to ask: is making sure deleted language files stay deleted really worth your time? In the end, the amount of space that’s taken up by these folders tends to be pretty small. If space is an issue, there more effective approaches to take.
A safe way to delete those language files would be to rename them (For example, from spanish.chm to spanish.chm.xxx) or move them to a temporary folder before removing them. Then, if you don’t have any problems after using the program for a while, it would be safe to remove the renamed files. If your program complains, then you can simply rename the files to their original names or move them back from the temporary folder.
Agree with Mark Jacobs. And it’s not just about saving disk space. Some programs actually start up a bit faster if you remove unneeded language files. It even happens with some Firefox add-ons and extensions. I always check the language files, rename unwanted files by adding .old as an extension and then testing them. (By always using .old as an extension, it’s always easy to find them later by simply searching for all *.old files.) Have rarely seen them being replaced, but have seen 3 programs which malfunctioned after removing those files, so I just renamed them back and all was well again. If the program works after removing them, then I delete those .old files after a while.