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why changing file extension while download?

  • 12 respostas
  • 2 have this problem
  • 1 view
  • Last reply by uncomp

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Hi,

i would be happy by getting support about the following problem:

When i try download for example a pdf/mov/zip etc. everything is fine. When i try to download an *.x83 file (this is a file extension for offers), Firefox seems to change the file extension by itself to *.xml. When i use a downloadmanager addon like "downthemall" or "flashgot" the extension from originally *.x83 changes to *.aspx. Downloading with internet Explorer ist OK. What i did since now is: reinstalling latest firefox + deleting profile folders, testing downloadmanagers, try to download from several internet sites offering *.x83 files. I noticed by checking google that several users got that prob but i didn`t find any solution.

Thank you very much for you help!

Greetings Dennis

Hi, i would be happy by getting support about the following problem: When i try download for example a pdf/mov/zip etc. everything is fine. When i try to download an *.x83 file (this is a file extension for offers), Firefox seems to change the file extension by itself to *.xml. When i use a downloadmanager addon like "downthemall" or "flashgot" the extension from originally *.x83 changes to *.aspx. Downloading with internet Explorer ist OK. What i did since now is: reinstalling latest firefox + deleting profile folders, testing downloadmanagers, try to download from several internet sites offering *.x83 files. I noticed by checking google that several users got that prob but i didn`t find any solution. Thank you very much for you help! Greetings Dennis

All Replies (12)

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does updating to firefox 23 help.

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Hi Waka, i installed the latest, v. 23 !

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delete the mimetypes.rdf file in the profile folder.

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Is this file going to be delete while uninstalling Firefox and deleting profile folders manually? If yes, i already did several times.

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This maybe a bug, ive never heard of such file type.

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Thank you for responding Waka!

The mimetypes.rdf is located in C:\Users\Administrator\AppData\Roaming\Mozilla\Firefox\Profiles\4fy4udy5.default ...so a deleted it several times.

I am working as an IT-Supporter, i do c new file extensions often. This extension is for online offers which have to be loaded in a viewer called wingaeb (http://www.schnittstellebau.de). When i download that file and rename it from test.xml to test.x83, wingaeb is able to open.

Any how, my firefox changes downloaded file extensions, many users got that problem...what can i do? As i can see, the Firefox Application Configuration doesnt give me a chance to add an extension.

I thought about a workaround like, when firefox is downloading an xml, rename to x83 automatically. Downthemall/flashgot are not able to...of course...!

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Ore are there any chances using about:config ?

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Yes, try filing a bug on this.

Earth4 modificouno o

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OK, THX !

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Hi uncomp,
According to this website .x83 files are in reality XML files.
http://www.gaeb.de/info13.php
Maybe these file are sent as XML files? The difference between IE and Firefox is that IE looks at the filetype to determine how to handle a file and Firefox looks at the MIME-type. If the MIME-type says that it is an XML file, then the file-extension may be ignored. Do you know the MIME-type for the downloads?

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You can Inspect the MIME database with the registry editor (regedit.exe) and do a search for that MIME type (file extension) via Ctrl+F.

Be careful with editing the registry as there is NO UNDO possible: all changes are applied immediately.

You can export key(s) in the registry editor before making changes.

You can check specific file extension keys (e.g. .jpg) in the registry with the registry editor.

  • HKEY_CLASSES_ROOT\.xxx

You can check the linked MIME type in the MIME Database.

  • HKEY_CLASSES_ROOT\MIME\Database\Content Type
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Hey knorretje, thank you for reply! In reality XML, waow, OK... Very good to know about the difference between Firefox and IE. I don`t know the mime type, but i am going to know!

Hello cor-el, thank you for reply too! THX for that tipps, I am going to check that tomorrow.


So i have to check the mime Type of the download and the mime type in regedit.