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Today I downloaded a .reg file, and Firefox made it a .reg.txt file. I downloaded a .zip file and Firefox made it a .zip.htm file. Both files worked fine when I fixed the extensions. What happened to Firefox? I haven't had this problem before.

Firefox 3.6.6, Windows XP Home SP3 w/all updates.

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What content type (MIME) is the server responding? You could examine it with an addon like Live HTTP Headers from – Andreas Jul 25 '10 at 12:36

Personally, I would install 7-zip,

However, if the Windows built in zip component is not working, you can try re-initilising it by going to the command prompt and typing the following commands:

regsvr32 zipfldr.dll

cmd /c assoc .zip=CompressedFolder

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I fixed the zip file by renaming it, and updated the problem description to address the real issue. – robert55 Jul 25 '10 at 11:53
Any idea why Firefox is now changing all the extensions on it's downloads? – robert55 Jul 25 '10 at 14:23
@robert55 no, I have never seen this. What site are you doing the downloads from and is it only this site or is it any site? – William Hilsum Jul 25 '10 at 14:34
Different sites. It's still doing it, with all file types except exe's. It's adding .txt, .htm, or .aspx to everything else. – robert55 Jul 26 '10 at 12:43
@Wil: you're not really answering Robert's question. The .reg.txt example indicates that this is a Firefox problem, at least has nothing to do with ZIP. – stevenvh Aug 10 '10 at 15:44

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