I read the topic "Notify your customers internet is down, monitor connectivity" on Mikrotik wiki (http://wiki.mikrotik.com/wiki/Notify_yo ... nnectivity)
but in this you need to add the address http://www.SOME-EXTERNAL-WEBSITE.com on the walled-garden.
when I create a new walled garden , I couldn't add any thing for dst. Address .
Also, I don't want to open the whole site so user can bypass the hotspot to that site; I just want to open for the exact link http://www.SOME-EXTERNAL-WEBSITE.com/im ... stemup.gif

So provide a path in the walled garden entry. Refer to the manual for how to.

So provide a path in the walled garden entry. Refer to the manual for how to.

i
I thought in the beginning that walled-garden will open access to the website by passing the hotspot but i know now now that it only show content in the lohin page.

I did and it is working but still the users has to open the hotspot login page by themself if there is no internet.

Another problem is that the browsers remember the last image. To confirm that is working, I first open the login page in firefox then in internet explorer. you can't tell users to clear their cookies just to see this.

Edit: it is only working on firefox but IE, chrome and safari shows the image for no internet

addition:
the site that I used is imageshack with link:
walled-garden setting
Action: allow
Server: My hotspot server name
Src. Address:
dst Address:
Method:
dst.host: http://img18.imageshack.us
port:80 (filled by itselfa after apply)
path: /img18/xxx/xxx.gif

If the site is the problem, please provide a good site to upload my image