Those kind of logs are kind of debug logs from Messenger or other Windows Live related services. They are made to troubleshoot all kinds of problems. Those files are very usefull for MS and should be send to them when they ask for it when you're filing a bug or when you contact support. But note that such logs can contain personal and private info (especially the
MsnMsgr.txt file!), so be careful not to publish them on public forums like this.
It depends a bit on your registry settings which logs are exactly made and where they are made.
In regards to the MsnMsgr.txt file:
This depends on the registry keys:
HKEY_CURRENT_USER\Software\Microsoft\MSNMessenger\LogFileName
HKEY_CURRENT_USER\Software\Microsoft\MSNMessenger\LogFilePath
By default (eg: if the above keys don't exist) the name is
MsnMsgr.txt and the path is your received files path in Messenger.
You could disable the creation of this log by disabling the connection logging of Windows Live Messenger:
Tools > Options > Connection > Advanced Settings > Save a log of my server connections to help troubleshoot connection problems.
Also see some old related posts
CookieRevised's reply to How can i record history of all users that login MSN.plus in my computer.
CookieRevised's reply to Messenger Plus! Live 4.60 is out
CookieRevised's reply to Can't sign in to MSN/Error 81000395
In regards to ???????0.log files (eg: Transport0.log):
The creation and location depends on the registry keys found under:
HKEY_CURRENT_USER\Software\Microsoft\Tracing
Logging depends on what services/clients are defined as subkeys under the
Tracing branch.
eg:
Windows Messenger 5.1 = RTCDLL
Office Communicator 1.0 = LCAPI
Office Communicator 1.1 = UCCP\Communicator
Windows Live Meeting = UCCP\LiveMeeting
Windows Live Messenger = UCCAPI\WindowsLiveMessenger
etc.
In each (sub)branch there is a
EnableFileTracing key (DWORD) which enables the creation of the log files and a
FileDirectory key (REG_SZ or REG_EXPAND_SZ) which contains the path where the specific log is created. The location of them does NOT depend on your received files path in Messenger!
Related log files are (but not limited to):
AudioCodecs0.log, AudioEngine0.log, ComAPI0.log, Common0.log, Crossbar0.log, Device0.log, Engine0.log, lcapi0.log, QualityController0.log, RawMedia0.log, RTP0.log, Transport0.log, VideoCodecs0.log, ...
where the 0 is the index of the last created file (also depends on some other registry key found under the same (sub)branch. But usually, and by default, this will always be 0 as only 1 file will be created).
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Beware: all these types of log files can contain quite a lot of personal/private data. Not only from yourself, but from your contacts too (eg: their email addresses). So please do not post such logs on public forums! I have never seen anybody -except Microsoft themself- being able to use such logs for proper troubleshooting anyways... So, please don't share them with anyone, except with MS when they ask for it.
Note: none of these log files have anything todo with adware, spyware or any kind of virus or other malware, despite what you may read on various other forums. They are logging and tracing files created by various MSN/Windows Live services to help debugging and error tracking and are not harmful in any way.
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