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I have a small PHP system I created for myself. This system contains a few .doc and .docx file documents. I want to be able to open them directly from the browser without downloading them.

I created a link: <a href="file:///c:/mysite/myfile.docx">myfile</a>. But Firefox does not open the link. href="http://localhost/myfile.docx" works fine - it offers me to download the file.

Any ideas on how I can do it? Do I need to change something in the Firefox options or security settings?

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up vote 3 down vote accepted

Both Firefox and IE8 support the File URI scheme.

Here are some examples valid for Windows systems, referring to the same file c:\WINDOWS\clock.avi


While the last is the most obvious and human-readable, the first one is the most complete and correct one.

Apparently (from the same url):

Mozilla browsers refuse to follow file URLs on a page that it has fetched with the HTTP protocol.


Mozilla browsers can be configured to override this security restriction as detailed in Mozillazine's "Links to Local Pages Don't Work".

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Thanks a lot! Although the file:/// URI schema did not worked in IE8 and Firefox, i used the extension in the link you gave and it solved the problem. – Aviv Feb 1 '10 at 13:59

Although the solution indicated in Links to Local Pages Don't Work was buggy for a while, it has been fixed.

For instance if the page with file://... links is served on localhost on port 49154, one solution is to

  • exit firefox
  • edit prefs.js, adding the lines

    user_pref("capability.policy.policynames", "localfilelinks"); user_pref("capability.policy.localfilelinks.sites", "https://localhost:49154"); user_pref("capability.policy.localfilelinks.checkloaduri.enabled", "allAccess");

    and possibly for https protocol:

    user_pref("capability.policy.trustable.sites", "https://localhost:49154");

  • restart firefox

File links should now be opened upon left click

(tested with firefox 45 under kde, for a personal weblog called elog)

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