Topic on Project:Support desk

Our company wiki has been working for years and has been updated to 1.26.3 a few months ago without problems. A few weeks ago it started downloading some pages instead of rendering them.

If the search term does not match the title of a page, the search result page is shown and clicking on one of the search result items works well.

If the search term matches the title of a page, pressing enter or clicking on the page title shown at the top of the list, downloads the page instead of showing it. Clicking on the Containing... link below the page name, then the search result page is shown and everything works well.

Clicking the Save page button after editing a page, the page will be downloaded. Canceling the download and clicking the Read link shows the page with the last editing properly saved.

The downloaded file is called index.php, it starts with the following text and has some binary data after that (I assume that's the compressed page content). I don't understand why there are the first two lines:

0
 
 HTTP/1.1 200 OK
 Server: nginx/1.10.2
 Date: Mon, 05 Dec 2016 17:16:45 GMT
 Content-Type: text/html; charset=UTF-8
 Transfer-Encoding: chunked
 Connection: keep-alive
 X-Content-Type-Options: nosniff
 Content-language: en
 X-UA-Compatible: IE=Edge
 Vary: Accept-Encoding,Cookie
 Expires: Thu, 01 Jan 1970 00:00:00 GMT
 Cache-Control: private, must-revalidate, max-age=0
 Content-Encoding: gzip
 Last-Modified: Mon, 05 Dec 2016 17:16:44 GMT

Here is the versions:

Product	Version
MediaWiki	1.26.3
PHP	5.5.38 (cgi-fcgi)
MySQL	5.5.51-38.2
ICU	4.2.1

Unrelated to your problem, but 1.26 is an old unsupported version without any security updates. Please strongly consider upgrading: Download.

Some more details:

• The problem reproduces when a link causes a redirect. For example clicking on the Random page link it does reproduce because it redirects to another page

• The problem reproduces 90-95% of the times, not 100%

This looks like a misconfiguration on the server, but try $wgDisableOutputCompression

Yesterday we just found out that the problem disappears after uninstalling BitDefender (disabling is not enough).

And now, thanks to you, I found out that disabling the compression the problem disappears, even if BitDefender is installed.

So we have a workaround while we try to understand why BitDefender causes the problem.

Thanks, Stefano