This might be your problem..
When you try to sign in to MSN Messenger, you may receive the following error message:
You cannot sign in to MSN Messenger 7.0 because you are connected to the Internet through a firewall that is using an HTTP proxy server.
Try the following to help resolve the situation:
The MSN Messenger HTTP gateway server may be temporarily offline. Try to sign in again after several minutes.
If you are using a firewall or router, make sure that MSN Messenger is allowed full access. Messenger uses port HTTP (80).
Clear the proxy settings in MSN Messenger:
- In the main MSN Messenger window, on the Tools menu, click Options.
In the left pane, click Connection.
Click Advanced Settings.
Delete all text in the Server, User ID, and Password boxes.
Click OK, and then click OK again.
Try to sign in to MSN Messenger again.
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