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How to disable MIME sniffing (Error opening zip attachement within Application/x-zip-compressed file)

  • 3 respostas
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  • Last reply by lumi.dan

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Try to open a mail from the web server provided by my ISP site and having an attachment shown as zip file. Cannot open it but an error occurred telling "the file is not a zip file or a downloaded file is corrupted,try to download again". Contacting the sender, he swear that is indeed a compressed file originated from an excel data base file. The "Help" tab from Internet Explorer recommend "to disable MIME sniffing" (what is this ?). Is something similar in Firefox, or other recommendation to open Application/x-zip-compressed file ? How to open such an attachment file in Firefox ? As a mention, I'm using Vista 32b , enough memory, I have installed WinZip software; any other zip files are opened correctly . Thanks Dan

Try to open a mail from the web server provided by my ISP site and having an attachment shown as zip file. Cannot open it but an error occurred telling "the file is not a zip file or a downloaded file is corrupted,try to download again". Contacting the sender, he swear that is indeed a compressed file originated from an excel data base file. The "Help" tab from Internet Explorer recommend "to disable MIME sniffing" (what is this ?). Is something similar in Firefox, or other recommendation to open Application/x-zip-compressed file ? How to open such an attachment file in Firefox ? As a mention, I'm using Vista 32b , enough memory, I have installed WinZip software; any other zip files are opened correctly . Thanks Dan

Chosen solution

Many-Many-Many Thanks. 7-zip solved the problem. The attachment shown as been a zip file can now be opened by 7-zip only. In fact there is a data base inside,readably with Excel or Database Viewer May I understand why ?

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Windows will need the file to have the correct extension type that is the dot and three or four letters at the end of a file (you may need to set Vista to display it - I have not used Vista). That file extension then needs to be associated with the correct program, use the assoc command, or use a right click and open with.

Firefox itself lets you choose what to do with different file types, so you may set it to a particular application, to ask, or to save the file.

There are also possibilities the file is corrupt or virus checking is interfering so note the additional troubleshooting steps in the links above.

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You can try to test the file with the 7-zip program or with another archive manager.

You can get the 7-zip program here: http://www.7-zip.org/
Run the installer and start the 7-zip file manager: 7zFM.exe
Browse to the file and click Test.

It is possible that anti-virus software is corrupting downloaded files or is otherwise interfering with downloading files.
Try to disable the real-time (live) scanning of files in your anti-virus software temporarily to see if that makes downloading work.

See:

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Chosen Solution

Many-Many-Many Thanks. 7-zip solved the problem. The attachment shown as been a zip file can now be opened by 7-zip only. In fact there is a data base inside,readably with Excel or Database Viewer May I understand why ?