Internet Explorer and Firefox do not stay in offline mode when localhost

Question

Localhost.

IE10 / Firefox 24

I am testing some caching options in my application and want to set Internet Explorer and Firefox in Work Offline mode. The browsers work fine for cached pages but whenever hitting a resource that's not cached, they immediately connect and download. I'm looking and searching but can't find a way to disable this auto-go-online behavior.

Is there a way to permanently set the browsers in offline mode and not auto-connect? I would just like them to display the 'not found' message when something is not available via browser cache.

UPDATE

Firefox seems to be a little better. It will stick to offline mode when browsing www content (it will not load pages), but will always load local server content.

IE10 always re-connects whether local or www.

In terms of localhost, i've tried plain old 'localhost', and mapped local domains (myawesomeapp.local)

Answer 1

I think I found an answer here: http://support.microsoft.com/kb/195730

Excerpt:

The offline mode that Internet Explorer starts in is determined by the registry data value "GlobalUserOffline." Setting this data value to 1 will cause Internet Explorer to start up in offline mode. Because this value is written with the current offline state when Internet Explorer is shut down, it is necessary to toggle the value manually through the Registry Editor before Internet Explorer is started, or to run a program that use the Registry APIs to change the setting.

For Windows 98, the "GlobalUserOffline" data value can be found under the following key:

HKEY_USERS.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Internet Settings

Under Windows NT 4 and Windows 2000, the key is as follows:

HKEY_USERS\SID\Software\Microsoft\Windows\CurrentVersion\Internet Settings

where SID is the security ID for the user who desires Internet Explorer to startup in offline mode.

Answer 2

The solution is to roll-back Internet Explorer's version to 8. Starting from IE9, there is the bug and the security hole in Internet Explorer: it go online when some application want access to Internet. It unexpectedly go online even if you open a local .mht file with JavaScripts (and, as I think, sends privacy-sensitive path to the file as a referrer). So, I deinstalled IE9 after an update, and live with IE8.

Also you can try to change proxy settings for the default Internet connection to 0.0.0.0

P.S. With the such security hole I haven't any desire to update Windows to any new version, and plan to switch to the some of Linux versions.