My DC++ is probably blocked by a firewall. How can I unblock?

Created by eMTee on on 2008-05-16
Keywords:
unblock firewall
Last updated by:
eMTee on on 2012-05-09

1. Do you have software firewall installed? Before you say no, double check it...

Newer Windows operating systems (XP with Service Pack 3, Vista and 7) have a built in firewall enabled by default. Moreover, many anti-virus suites include firewall component (like Norton, McAfee, CA, Eset, Kaspersky, F-Secure, etc..) with their "typical" install method. So you can still have a firewall running even if you've never installed a separate firewall product or never seen a slight sign of its operation.

2. Do you think you have enabled DC++ in your firewall? Before you say yes, double check it...

Most firewall software inform you when a newly installed program tries to access the Internet. At the same time they usually provide a way to make an exception for a particular program, mostly in form of a popup dialog. However, there are cases when a firewall software set up such a way that it should remain quiet and block every new software installed. In this case you won't see any warning message, etc... just problems or error messages inside the program beeing blocked.

It may also sounds weird but despite you once enabled DC++ in your software firewall, after a version upgrade, the firewall could block access of DC++ again. It can happen since one of the main purpose of a software firewall is to block unwanted or (abnormally) modified programs accessing the Internet from your computer. In some firewall products this feature called Application Control or something similar. This app control function keeps tracking your applications' integrity and if it detects any modifications in the binary code of an application (which can be the sign of infecition, etc..) then it may blocks the access of the program from that point. As during a version upgrade the program binaries are obiviously change this makes some poorly designed firewall software to block the new version. Depending on the settings the blocking of the new version often happens quietly, without any information shown by the firewall application.

3. How do I check if my DC++ blocked?

There can be many reasons why you simply can't connect to hubs therefore a better method to check if your DC++ is blocked is to go the Help/About menu inside DC++ and check if DC++ is able to download its Latest Version number info (bottom box of the window) from the Internet. After the About dialog opened a version number should appear in this box whithin a few seconds.
You can also check wether DC++ is able to download hublists or not. Open the View / Public Hublist menu; to force DC++ to download hublists instead of getting them from the local cache, select a hublist and press the Refresh button. Try more hublists.
If you get error messages during both of the operations above while you still able to browse the Internet with your web browser without problems this means that your DC++ is probably blocked by a firewall.

4. How can I unblock DC++?

The exact method varies product by product. Best practice is to exit DC++ and completly remove the according exception rule from the firewall. In most cases at the time of the next start of DC++ you'll get a popup window from the firewall where you can re-enable DC++.
You can find configuration method for some widely used firewalls here : http://www.dslreports.com/faq/dc/3.1_Software_Firewalls
Another tip: if you have any third party software firewall istalled then make sure you have the internal Windows firewall is disabled.

5. Where can I get more information about unblocking DC++ in different types of security software?

There's an alternative FAQ in this topic in the built-in help of DC++ (online at http://dcplusplus.sourceforge.net/webhelp/faq_unblock.html )