There are several things that could affect your ability to connect to the network.

1. You don't have a connection to the internet from your machine.
2. You are attempting to connect from a school or workplace that has recently blocked access for these types of applications.
3. You have recently installed firewall software on your machine.

Essentially, you haven't provided enough information about your configuration (when it worked) and what changed between it not working.

This information could be useful in helping to determine what's happening to your connection.


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