Android SDK Manager won't update: connection to https://dl-ssl.google.com refused

This is the same problem as a number of other have reported, e.g.

Failed to fetch URL https://dl-ssl.google.com/android/repository/addons_list-1.xml, reason: Connection to https://dl-ssl.google.com refused

Android SDK Not Updating Packages

Android SDK Manager gives "Failed to fetch URL https://dl-ssl.google.com/android/repository/repository.xml" error when selecting repository

But all of the suggested solutions either aren't relevant or haven't worked.

My problem is I get a connection refused error whenever I attempt to update the Android SDK Manager. This is the SDK Manager's log output:

Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Fetched Add-ons List successfully
Fetching URL: https://dl-ssl.google.com/android/repository/repository-7.xml
Done loading packages.
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Failed to fetch URL https://dl-ssl.google.com/android/repository/addons_list-2.xml, reason: Connection to https://dl-ssl.google.com refused

Entering https://dl-ssl.google.com/android/repository/addons_list-2.xml into Firefox just times out - I don't get an XML document.

I've tried it with and without the force http:// option with no luck. This is from home, I'm not using any kind of proxy server and I don't have a firewall set up.

Something else I tried (in order to eliminate my machine as the source of the problem) is entering https://dl-ssl.google.com in a web browser on another computer that uses the same internet connection (Acer laptop w/ Win7 64-bit). The connection times out on the other computer as well, which almost leads me to think my IP is blacklisted on the server somehow (I have no idea how that would have happened) or it's an ISP issue.

So my question is how can I get SDK Manager to update? If my IP is in fact being blocked by Google's server for some reason, is there anything I can do to get around it? E.g. by routing through some kind of proxy? Are there any mirrors for dl-ssl.google.com?

Environment info: I'm using ADT Rev 21.1 on Kubuntu 12.04.2 LTS.

The solution for me was just to keep retrying. The easiest way I found was to periodically hit refresh in my browser and once XML was returned, switch to Eclipse -> SDK Manager. For whatever reason it appears my IP address block is being severely throttled by https://dl-ssl.google.com. Hopefully a Google engineer can check out this server's configuration (denyhosts settings??) as it seems to be an ongoing problem with a number of topics in Google groups