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What Is µTorrent?


Micro-Sized Yet Feature Filled

µTorrent is the world's most popular BitTorrent client.
Most of the features present in other BitTorrent clients are present in µTorrent, including bandwidth prioritization, scheduling, RSS auto-downloading and Mainline DHT (compatible with BitComet). Additionally, µTorrent supports the Protocol Encryption joint specification (compatible with Azureus 2.4.0.0 and above, BitComet 0.63 and above) and peer exchange.


Resource-Friendly

µTorrent was written with efficiency in mind.
Unlike many torrent clients, it does not hog valuable system resources - typically using less than 6MB of memory, allowing you to use the computer as if it weren't there at all. Additionally, the program itself is contained within a single executable less than 220 KB in size.


Skinnable and Localized

Various icon, toolbar graphic and status icon replacements are available, and creating your own is very simple. µTorrent also has support for localization, and with a language file present, will automatically switch to your system language. If your language isn't available, you can easily add your own, or edit other existing translations to improve them!


Actively Developed and Improved

The development team puts in a lot of time working on features and making things more user-friendly. Releases only come out when they're ready, with no schedule pressures, so the few bugs that appear are quickly addressed and fixed.


Changelog:


1.9 is now 2.0, and we've hit beta!

Release Notes:


We've added UDP tracker support!


uTP has been improved significantly over the previous alpha, with many bugs fixed and performance improvements. It's no longer hidden in Advanced settings.


The setup dialog has been overhauled to make it much easier to use and with a built-in speed test. It's still not quite complete yet, but this will give you a good taste of what we're up to with it!


A new transfer cap feature has been added to track bandwidth usage, along with graphs to show your usage.



Feature Overview:

UDP trackers are a different protocol for tracker communication that uses significantly less processing power on the tracker end.
It's important for us to support this because trackers have limited resources, so this should allow them to support many more users with their current hardware and not crash under the load.

uTP is an alternative communication method for BitTorrent traffic that allows the client to automatically regulate its bandwidth usage to avoid adversely impacting your internet connection. This will allow you or other users on the network to download their torrents but still allow others on the network to function with little difference. This does not require any additional setup.
In addition, uTP in this version has added its own form of STUN, a method of getting incoming connections without direct connectivity to the Internet.
This allows µTorrent to punch holes through routers and firewalls to increase connectivity and improve speeds. It is even possible to connect two firewalled peers through uTP's NAT traversal feature.

The transfer cap settings were added in response to various users who have ISP-mandated caps on how much data they can download/upload in a month.
Now you can track your usage in MB (with a handy graph to visualize it) and even configure µTorrent to stop torrenting once the limits are exceeded.
Currently, you can configure the time interval, the data cap and whether it should stop based on only download, upload, or both combined.
As a privacy notice, this traffic data is not sent back to us or anyone. 



2009-11-25: Version 2.0 Beta (buid 17427)


Fix: Fixed rare crash when using magnet links

Fix: Fixed crash when super seeding a torrent without metadata

Fix: Fixed handling of a uTP edge-case


Change: Complete upload-only extension support




2009-11-18: Version 2.0 Beta (buid 17341)


Fix: Various GUI crash bugs

Fix: Accept magnet links through add-url webUI




2009-11-12: Version 2.0 Beta (buid 17273)


Fix: More strict https connection state management for halfopen accounting.


Fix: Problem during install toolbar offer


Change: Relaxed the requirements on bencoded integers to parse some broken torrents




2009-11-06: Version 2.0 Beta (buid 17188)


Change: Added checks for heap corruption that caused crash in uTP

Change: Improved stability by making all executable pages not writable


Fix: Fixed stack overflow when copying peer list

Fix: Fixed allocation regression in connection to peers




2009-11-03: Version 2.0 Beta (buid 17127)


Change: Enable multiple instances of the client to run on multi-user machines (e.g. fast user switching)


Fix: Fixed uTP crash in edge condition

Fix: Fixed crash when icmp.dll wouldn't contain the expected functions

Fix: Fixed crash when closing add torrent dialog while dragging a column


Change: The Speed guide will now reject ports listed in bt.no_connect_to_services_list

Change: Add an upgrade message if a buggy version of nvLsp is detected


Fix: Don't take the total number of connections into account when connecting to trackers


Change: Increase default transfer cap to 250 GB/month


Fix: Accounting of halfopen https connections would cause uT to stop making new connections


Change: Made the DHT compatible with future extensions


Fix: Sometimes the &ip= parameter sent to trackers would be incorrect

Fix: Correctly order bencoded dict items in extension handshake message

Fix: Fixed holepunch error handling and support detection

Fix: Check invalid ports and IPs in the DNS resolver to avoid using them




2009-10-12: Version 2.0 Beta (build 16850)


Change: Revert change where asserts are active in release builds




2009-10-10: Version 2.0 Beta (build 16835)


Fix: Various polishing on the setup guide

Fix: Potential crash related to TLS not being initialized


Change: Disable installer for Wine

Change: Balance CDNs to download updates


Fix: Fixes bug where magnet links wouldn't work if PEX was disabled

Fix: Potential crash in network code

Fix: More crashes when using magnet links





2009-09-25: Version 2.0 Beta (build 16666)


Fix: Port settings saved in Setup guide


Change: Updated helpfile code to be forward compatible with changes


Fix: Fixed torrent creation bug

Fix: Fixed crash introduced in last build

Fix: Fixed rare crash when parsing messages




2009-09-24: Version 2.0 Beta (build 16625)


Change: UI improvements in setup guide


Fix: More setup guide crash fixes

Fix: Fixed rare holepunch crash


Change: Collect stats on holepunch performance




2009-09-17: Version 2.0 Beta (build 16546)


Fix: Fixed crashes in setup guide

Fix: Graying out custom toolbars with transparency


Change: Disable Ask for unsupported 64-bit Windows





2009-09-14: Version 2.0 Beta (build 16515)


Fix: Fixed crash in setup guide

Fix: Fixed UDP-tracker crash when dns resolution would fail


Change: Use user-supplied port in Setup Guide, save auto-portmap prefs.

Change: Added European Servers in Setup Guide

Change: New Icons in Setup Guide


Fix: Improper mutex accounting in hang detector

Fix: Crash when creating torrents





2009-09-09: Version 2.0 Beta (build 16407)


Fix: Fixed handling of invalid udp tracker responses




2009-09-04: Version 2.0 Beta (build 16394)


Fix: Bugs where have messages would not be remebered for magnet link downloads

Fix: Buffer overrun vulnerability


Change: Conservative network locking in installer


Fix: Rare crash in low level network read and write

Fix: Fixed crash in udp tracker connection with unresponsive DNS

Fix: Improved out-of-memory error handling in disk thread

Fix: Installer crash after download


Feature: Stop setup guide tests without exiting dialog


Fix: Crash when peers disconnect from a magnet-link torrent right as we received the metadata

Fix: Fixes bug where magnet links wouldn't work if PEX was disabled


Feature: Added ability to re-run setup tests


Fix: Fix crash when using magnet links and a peer is failing at a particular point

Fix: Fixed negative allocation in RequestChunks() for web seeds


Change: Updated bandwidth presets in Setup guide


Fix: Fix startup race condition between network and disk I/O thread


Change: Optimization added to speed up torrent creation




2009-08-20: Version 2.0 Beta (build 16222)


Feature: Added versioned help files.


Fix: Setup guide fixes

Fix: Installer with UAC

Fix: Allow UDP trackers in the first tier when creating torrents

Fix: UDP Tracker retries three times instead of two

Fix: potential crash in installer

Fix: Crashes when removing labels

Fix: Selection of labels over 256 characters in length

Fix: Multiple HTTP download crashes

Fix: Http seed fix for multifile torrents

Fix: uTP connections that are upload rate limited will not have their max window size grow indefinitely

Fix: Vista and Windows 7 FW rules are created for all profiles





2009-08-10: Version 2.0 Beta (build 16126)


Fix: Tracker requests are not invalid anymore




2009-08-04: Version 2.0 Beta (build 16081)


Change: Disable toolbar offers for Wine installs


Feature: New Setup guide & Speedtest.


Change: Uninstaller is added to all user profiles


Fix: Crash when assigning new label to torrents from RSS


Change: Incomplete downloads sort after completed downloads if sorting by "Completed On"


Feature: Add Moldova to peer flags


Change: Added upnp host cache to speed up upnp nat resolution on misbehaving routers


Fix: Maintain category list selection on update for some edge cases


Change: If selected, install start menu and desktop shortcuts to all users instead of only current user


Feature: Grayscale disabled toolbar buttons


Fix: Fixed uTP selective ack bug (would cause connections to stall and time out)

Fix: Fixed uTP fast re-send bug (would sometimes re-send packets that shouldn't be re-sent)

Change: Prompt to take associations in installer only if any others exist


Fix: Buffer overrun vulnerability in create torrent dialog

Fix: uTP recovers faster after timeout


Feature: uTP supports window sizes smaller than the packet size


Change: Reduced uTP overhead slightly by ramping up packet sizes at lower rates


Feature: Enable and disable toolbar buttons according to selected torrents


Change: UAC must be completed to install in Vista or higher


Fix: Memory leaks in main window, protocol associations, settings dialog, general tab


Change: Tweaks to Ask toolbar offer


Feature: UDP tracker support


Fix: Only change run on startup if installer is shown


Change: Added support for 3:rd party applications to more easily be configured to access the uTorrent web UI, i.e. to pair the applications

Fix: Make "alternate upload rate when seeding" apply when the seeding is set by the scheduler

Fix: Align "Web Seeds" in torrent creation dialog

Fix: Translated strings in uninstaller

Fix: Http seeds would not reconnect after stopping and starting torrent

Fix: Http seed for multifile torrents

Fix: Regression in 15562 that caused frequent crashes


Feature: New installer with EULA, file association


Fix: uTP issue on low-latency high-throughput networks

Fix: Copying long filenames to clipboard no longer results in garbage or crash

Fix: Fixed web seed support for multi-file torrents


Change: Torrent whose "Force Recheck" is greyed out will not recheck when asked through multi-torrent selections

Fix: When adding torrents through URLs via commandline, we would always open the add torrent dialog

Fix: Handle multi file torrents with web seed urls that incorrectly don't end with a slash

Fix: Make sure web seed urls end with a slash for multifile torrents

Fix: Setup Vista firewall

Fix: Remove settings on Vista during un-installation


Feature: New "Transfer Cap" pane in Preferences

Feature: uTP can be enabled or disabled using "Enable bandwidth management" checkbox in Preferences


Fix: Check at startup for incompatible versions of NVIDIA nForce firewall.


ED2K Link:
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