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Can very old language package files in C:\ProgramData\O949 be removed without causing problems?

Thunderbird2015

Hello all,

During clean-up of my laptop I noticed 31 language package files in C:\ProgramData\O949. File names look like: langpack-en-US@firefox.mozilla.org, and they all originate from 23-Jan-2017 so I guess they're very old files which might be relevant anymore. As these 10,058 files occupy 56 MB I'd like to remove them from my laptop.

Does anybody know if such task is wise, not harming current running FF v131.0.3?

Hello all, During clean-up of my laptop I noticed 31 language package files in C:\ProgramData\O949. File names look like: langpack-en-US@firefox.mozilla.org, and they all originate from 23-Jan-2017 so I guess they're very old files which might be relevant anymore. As these 10,058 files occupy 56 MB I'd like to remove them from my laptop. Does anybody know if such task is wise, not harming current running FF v131.0.3?
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Выбранное решение

Hello TyDraniu,

Well, it took a little longer than 2 weeks, but as I didn't notice any behavioral change the last months I per today removed mentioned files, and consider this topic as solved.

Все ответы (5)

Hello Mark,

I reviewed both links you provided, but they're more about troubles with multiple language / dictionary problems and that's not my real problem. Will wait some more days to see if another solution pops-up, and then I'll delete the files (starting with the languages I don't use or am not able to understand).

Thanks anyway for your quick response!

This folder C:\ProgramData\O949 doesn't look like anything important for Firefox. Perhaps it's old temp or some leftovers of installation or update process.

Hello TyDraniu,

I changed the directory name to C:\ProgramData\old_filename_O949 expecting FF can't recognize this directory anymore. Will run FF the next 2 weeks and see if any topic occurs. If not, I'll delete the full directory. Keep you informed.

Выбранное решение

Hello TyDraniu,

Well, it took a little longer than 2 weeks, but as I didn't notice any behavioral change the last months I per today removed mentioned files, and consider this topic as solved.