Thread:Project:Support desk/Update fails with 'Error code: ERR CONTENT DECODING FAILED'/reply (4)

Is it at all possible to use the command line update.php script to update your wiki? (I assume this is a problem only during the upgrade, not during normal browsing of your wiki).

Its kind of odd getting this error during the installer, as MediaWiki is already supposed to be disabling output compression during install.

If you can't make the command line installer work, I guess it would be time for debugging steps - Do you have any errors in php error log. Can you look at the headers of the relavent request (using developer tools that come with your browser for example) and see what the content-encoding header for that page. Can you see what the raw response body (what the web server actually sends) for that page, and if so, is it really just gzipped twice, or something else.