Make sure you are running the latest version of your BT client.
Start your BT client and look at the "Help --> About" to find out what version you're currently running.
Go to your BT client's website and find out what the latest stable version is, and if necessary download and install it. If you needed to upgrade, we suggest you reboot before proceeding with this guide.
If you're still getting slow downloads, continue reading (or click here).
Change PORTS - Your ISP may be limiting your download speed
Some ISPs are limiting download speeds by controlling the bandwidth allocated to traffic using the default Torrent ports, which are 6881 to 6999.
This is not just a problem for those who have nasty ISPs, it affects everybody. To avoid ISPs from damaging the efficiency of a torrent with their controls, some stringent tracker owners are blocking users trying to connect on the standard ports.
So whether your ISP is limiting you or not, all Torrent users should stop using the default ports.
For simplicity, this guide recommends the use of port 16881 (any number over 10000 is usually fine). Adding a 1 to the start is simple administratively, and is in a range unlikely to be used by other programs.
You then need to set up your client to use the new port (16881).
AZUREUS
Tools -> Options -> Connection
Add a "1" before the current listen port number. For example, 6881 will now be 16881.
OTHER CLIENTS
via whatever settings are equivalent
Whatever client you use, make sure you update anywhere else you have entered the port numbers to account for the change (e.g. port forwarding if you've already configured that).
By completing this section, you have helped to avoid problems later down the line, but this will not solve the majority of slow downloads. Therefore, continue reading (or click here).
Configure Your ROUTER and FIREWALL
If you are on a LAN with a router, hardware firewall, or software firewall (such as Zone Alarm), you need to configure it. You need to forward Torrent connection ports to your specific PC on the LAN. Click here for a guide on forwarding your ports and configuring your firewall.
Return to this guide when you've completed the forwarding and configuration (or click here).
Perform a speed test, and adjust your speeds
Try limiting your upload if you have ADSL/DSL. Sometimes torrents can try to upload so much that it floods your upload, making it difficult for incoming connections. Slyck.com explains further:
It might seem strange to hear that your upload speed can directly affect your download speed, but it can, and quite dramatically. The reason behind it is based on the way the Internet works. When you download a file (or in this case, chunks of a file), your computer sends a tiny message back to the source computer, called an ACKnowledgement packet. These ACK packets tell the source computer that chunk #1 has arrived OK, please send #2. When #2 is down, it sends another, and so on. The source computer will not send #3 until it gets the ACK from #2. It uses a small amount of your upload bandwidth to do this. This works fine when downloading files off the Internet, but with P2P, you tend to upload as well.
This is especially true with torrents – because you upload as well (you're always seeding while you're downloading). If done efficiently, downloads can be very fast. The problem lies with the fact that you upload *so much* that the ACK's do not get sent out fast enough, which slows your download. Also, depending on your actual speeds, you may find you need to limit the number of torrents simultaneously running (to 1-4 depending on your connection).
The simplest way to solve this is to limit your upload bandwidth. 80% of the maximum is usually recommended:
Determine your real maximum UPLOAD speed at www.testmy.net by doing the upload speed test (while doing NO downloads or other internet processes).
Change your maximum UPLOAD speed settings in your BT Client to 80% of the test results (following the guide at http://azureus.aelitis.com/wiki/index.php/Good_settings - it's written for Azureus, but the calculated numbers are applicable to any client). For example:
DOWNLOAD UPLOAD
ISP
advertised
connection test
results set your "kBps/s
global max. speed" to test
results set your "kBps/s
global max. speed" to
30 Mbps
= 3.75 MBps
= 30720 kbps
= 3840 kBps 3603 kBps 2880 kBps 688 Kbps
= 86 kBps 65 kBps
128 kBps 115 Kbps
= 14 kBps 11 kBps 115 Kbps
= 14 kBps 11 kBps
You should also limit your DOWNLOAD bandwidth to 80% (based on the same table above), since you need space to send requests from your browser as well as from your bit torrent program
Be very careful when dealing with speed numbers expressed in Mbps, MBps, kbps or kBps - that capital "B" makes a big difference:
2 Mbps (Mega bits per second - your ISP may tell you that's your speed because it "sounds" faster)
= 0.25 MBps (Mega Bytes per second - 8 bits per Byte)
= 256 kBps (Kilo Bytes per second - 1024 k in a M (don't ask))
= 2048 Kbps (Kilo bits per second - your ISP may tell you that's your speed because it "sounds" faster)
If you're still getting slow downloads, continue reading (or click here).
Remove the limit of TCP connections in Windows XP SP2
How do I know if I'm on Windows XP SP2?
Go to "My Computer" ---> Right click --> Properties --> General Tab --> System: will indicate whether you have SP1 or SP2.
I'm on SP2
With SP2, Microsoft introduced a limitation to the number of TCP/IP connections per second that can be established by, for example, your BT Client. This can restrict your speeds considerably, as you need to connect to a great number of peers to download fast.
There is, however, a simple workaround to this problem. Simply download, extract and run this patch to remove the limitation.
You are not causing any harm to your computer by applying this patch (see details here that explain that this is NOT a virus ), but still do this at your own risk.
Note: If you have applied this patch in the past (but not in the last month), you should re-apply the patch. Windows Update now "fixes" (un-applies) the patch for you without telling you.
If you're still getting slow downloads, continue reading (or click here).
NAT Errors
How do I know if I have a NAT error problem?
You might not have a problem at all. Before continuing with this section, run a test.
AZUREUS
Start to download a good healthy torrent using your chosen client. Leave your torrent running for at least twenty (20) minutes. Look in the "Health" column (a full list of the different colours can be seen here).
If it is Green then all is OK. Your slow downloads are being caused by something else - click here.
If it is showing a yellow spot after twenty (20) minutes, then stop and restart the torrent and wait another twenty (20) minutes. If it's still yellow then rerun the test again on at least 2 other healthy torrents. If it persists as yellow on all healthy torrents, then run the NAT test:
PLEASE NOTE: The Azureus checker can report a false NAT error if you are running PeerGuardian or Protowall. Make sure these are disabled before using the Azureus wizard.
Select "Tools" -> "NAT / Firewall Test"
The default TCP listen port is 6881. If you have changed the listening port, enter the new port in the "Incoming TCP Listening Port."
Press "Test"
If the result is "OK", then your slow speeds are being caused by something else. Click here to proceed.
If the result is "NAT Error," please continue with this section.
OTHER CLIENTS
via whatever settings & tests are equivalent - uTorrent will tell you if you're having a NAT problem
If the result is "OK", then your slow speeds are being caused by something else. Click here to proceed.
If the result is "NAT Error," please continue with this section.
You truly have a NAT error
Torrents work on a credit system. By uploading parts of a file other people, they allow you to download parts of the file from them. This is Torrents anti-leech measure, however, if you have a problem with your NAT (Network Address Translation - anything between you and the internet, such as a router or firewall), you will not get credit for what you are uploading. The only downloading that you can do is from people who upload a small amount to you in the hope that you will return the favour. Since their client will not recognise your response if you have a NAT problem, then they will stop uploading to you shortly after. This is what is causing your problem. You may also notice that torrent speeds go very high for 5mins, before slowing back down to 0-5kb/s.
You need to configure your computer and/or network to accept incoming Torrent port connections. The tracker port is 6969. If this port is not correctly configured, downloads will not start at all. The download/upload ports used in this guide are 16881-16889. It is these ports that are causing your problems - continue this section.
Azureus - switch off UPnP
If you are not using Azureus, click here.
Universal Plug and Play (UPnP), it is an Azureus feature that works with some compatible routers to open the required ports automatically. However, some routers, even if they are compatible with UPnP, have problems with this.
Tools -> Options
Expand "Plugins" on the left hand tree.
Select "UPnP"
Deselect "Enable UPnP"
If you're still getting slow downloads, continue reading.
Configure Your XP Firewall (ICF: Internet Connection Firewall)
Please go to the appropriate sub-section:
If you have Windows XP
If you have SP1 click here
If you have SP2 click here
Otherwise click here.
Configure ICF in SP1
Open up your "Network Connections". Right click on your internet connection or LAN connection and select "Properties".
Select the "Advance" tab
If the "Internet Connection Firewall" is not ticked, then this is not your problem. Move onto the next section "Configure Your Router".
If it is ticked, continue this section.
Click "Settings…"
On the "Services" tab press "Add…"
Description of service = Torrent
Name or IP address of the computer hosting this service on your network = 127.0.0.1 (this means "the local machine.")
External Port number for this service = 16881
Internal Port number for this service = 16881
TCP/UDP = TCP
Press OK.
Check your port
AZUREUS make sure that "Tools -> Options -> Connection -> Incoming TCP Listen Port" is equal to 16881.
OTHER CLIENTS via whatever settings are equivalent
If you're still getting slow downloads, click here.
Configure ICF in SP2
Open your Windows Control Panel and select "Security Centre."
Scroll down to the "Manage security settings for:" section and select "Firewall"
Decide whether you want to keep the firewall on or off. Make an informed decision based on more than the information provided by Microsoft.
If you decide to switch it off, then do so and move onto the next section "Configure Your Router".
Otherwise, continue this section.
Select the "Exceptions" tab.
Select "Add Port…"
Name: = Torrent (or anything of your choice)
Port number: = 16881
TCP/UDP = TCP
Press OK.
Check your port
AZUREUS make sure that "Tools -> Options -> Connection -> Incoming TCP Listen Port" is equal to 16881.
OTHER CLIENTS via whatever settings are equivalent
If you're still getting slow downloads, continue reading (or click here).
Multiple Torrent users on a LAN / Wireless connection
In a home (or office/school/etc) (wireless or wired) network, multiple users may be on the same LAN (Local Area Network). The same port can not be forwarded to different computers, so decide who gets which ports, for example:
192.168.0.2 = 16881
192.168.0.3 = 16882
etc.
Set up your router or ICS to forward the ports to the chosen computers.
Now you need to set up the BT Clients:
AZUREUS Each computer only needs one port forwarded to it.
Tools -> Options
"Connection" on the side menu
On "Incoming TCP Listen Port" enter the port number that is being forwarded to that computer. Taking from the above example, computer 192.168.0.3 would enter 16882.
Repeat for all the users on the LAN
OTHER CLIENTS via whatever settings are equivalent
If you're still getting slow downloads, continue reading (or click here).
Freezing
Symptoms: Torrent starts well, achieving good speeds. Speed then falls to zero. This is followed by the client freezing, computer freezing and/or loss of internet connection.
Possible solutions:
This is a common problem with ZoneAlarm 5. Switching it off may not solve the problem. It is recommended that users switch to version 6.
Norton Anti-virus sometimes tries to scan the chunks which make up the files you are downloading. Get yourself a decent anti-virus program like AVG or Avast!
Also, you may need to limit the number of peer connections to something (try 60):
AZUREUS Tools -> Configuration -> Connection -> set the "Maximum number of connections per torrent" to 60.
OTHER CLIENTS via whatever settings are equivalent