Many users experience problems sending and receiving via DCC using mIRC. There are a variety of reasons for these problems, some of which are easily resolved and others not.
DCC Receive Problems
These are the easiest to resolve. There are only a few reasons you may not be able to receive a file from another person on IRC.
I. Symptom: You never even see the DCC send.
Four possible causes for this.
A.) You do not have the file extension e.g. *.mp3 added to the file types NOT to ignore under FILE >> OPTIONS >> DCC >> FOLDERS. If you look in your status window you will see a msg stating that the DCC was rejected...
DCC Send from murf rejected (kne100tx.exe, file type ignored)
The resolution is to disable the ignore totally (not recommended for inexperienced users) or just add the filetype to the list.
NOTE: this feature was added in mIRC v5.7 and there are some variations in how this feature works from v5.7 to v5.9
B.) You have DCC gets disabled under FILE >> OPTIONS >> GENERAL >> LOCK.
C.) You have ignore on. Type: /ignore off in any window.
D.) CTCP event handling is off. Type: /ctcps on in any open window to turn it on.
II. Symptom: You see the DCC send but get an error "You do not have permission to open this file."
This is because you cannot write the file out to disk. This could be because the disk is full or because you do not have permission to write to that directory. Try saving to a different directory.
To change the default save locations, look under FILE >>OPTIONS >> DCC >> FOLDERS and edit as needed in the 'DCC Get Folders' drop down menu.
III. Symptom: You get the error "Unable to connect"
This is the senderís problem. See below.
DCC Send Problems
When you initiate a DCC send or chat, you send a CTCP to the person you are DCCing with your IP information and then open a port to listen for their reply. The receiver must then be able to find the IP address and port you are listening on. Only when you receive the acknowledgement back from the person receiving, is the DCC send connection established.
Therefore DCC send problems have a single root cause. The receiver cannot reach your system on the appropriate port. However, there are a variety of reasons for this. Since more and more people have increasingly complex home networks, it is not possible to describe resolutions to every issue in detail.
Here are the solutions to the most common problems:
Symptom: All send problems have the same symptom; the receiver simply gets an "Unable to Connect" error message. From your end it appears as though the DCC was never acknowledged.
There are two general cases,
∑ Your IP is set incorrectly in mIRC
∑ Your IP is set correctly but you still can't DCC send
You can determine which is your problem by typing the following commands...
NOTE for cable users: It is possible that /dns may not work correctly for you, try /userip your nick instead.)
The results from this should match. The dns results will show up in the status window and will look something like...
*** Looking up cc388468-b.mcmb1.mi.home.com -- ***
Resolved cc388468-b.mcmb1.mi.home.com to 18.104.22.168
...Now typing //echo -a $ip should return in the active window...
Solution for Mismatched IP Addresses:
Previously, the most common DCC send problem was mIRC not detecting the correct IP address for your system. MIRC has gotten much better at detecting the correct IP address and this problem is far less common. Therefore your first step should be to make sure you are running the latest version of mIRC. If the problem persists, it is usually related to network configuration issues and is not resolvable without some reconfiguring of the network.
Try the following steps depending on which version of mIRC you are running...
For mIRC v5.7 and above...
1. Type: /localinfo -u in any open window
For mIRC v5.6x...
2. Go to FILE >> OPTIONS >> CONNECT >>LOCAL INFO.
3. Clear the local host\IP address,
4. Check always get local host.
5. Select the server method
For older mIRC versions, upgrade, but failing that...
2. Find the local info under the File menu
3. Clear the local host\IP address
4. Check always get local host
5. Select the server method
Now check your IP again, if the results match you are hopefully fixed. If not, you are probably on a LAN and you cannot fix your DCC send without assistance from the network administrator.
Solutions when IP Addresses Match:
I.) You (or your company) are running a firewall/proxy. These block attempts at inbound connections, itís their job. This effectively kills DCC sends unless you configure them correctly. If you have set these up at home, then you will need to figure out how to open the DCC ports. If you are at work or school, you will have to bribe your network admin to open the ports. MIRC defaults to 1024~5000 for DCC ports, but this can be set to anything and if you have to open ports on your firewall, a smaller range is advisable.
II.) You are using a Linksys/Netgear/Other home DSL router. This equipment is essentially a firewall and has the same effect of stopping attempts at inbound connections. Here, too you will have to figure out how to open individual ports. For the Linksys BEFSR41 or 11 try these steps:
1. Logon to your router via http://192.168.1.1
2. Disable 'Block WAN Request'
NOTE: Be aware that this workaround turns off the firewall feature of your router and is not the best solution. Learning how to forward individual ports is the best solution (Check the help for Virtual Servers if your documents say nothing about Port Forwarding).
III.) You are connection sharing. If you use connection sharing (Wingate, ICS) it is possible to get DCC send working. A tutorial for this can be found at, http://www.borg.com/~chuck/
IV.) You are running WindowsXP. WindowsXP has a built-in firewall that unless it is configured or disabled, will prevent DCC sends. Right click My Network Places->properties->Right click connection->properties->advanced tab->uncheck Internet Connection Firewall. A tutorial with pictures can be found at http://toidyman.net/xp-dcc/5.htm
If you made it this far and have no clue what you just read, don't feel bad. There are many solutions available to the home user that are, by design, simple to install. However, the art of network configuration is never simple, you should contact your network administrator, ISP or an online help channel, such as #help.
Thanks to murf for his help with this article.