Remote profling is failing due to an error "Tcp channel protocol violation: expecting preamble"

Hi There,

I am trying to remotely profile a website (IIS app) using its URL which is hosted on a Web Server within our organization (by means of NTLM authentication).

Before remote profiling attempt, I've ensured following things are fine on local & remote machines:

1) Firewalls are turned off on both computers

2) RemoteAgent is successfully registered on remote machine

3) .Net frameworks are in sync on both machine and their version is correct (v4 in this case)

4) Usergroups have sufficient rights for access (trust recognition)

5) IIS service is enabled on local machine

6) Host name and password is correct in profiling configuration

7) Remote machine is up and running fine (I'm able to browse URL on my DotTrace machine)

But DotTrace profile is unable to establish connection with remote machine due to following error(s):

"TCP Channel protocol violation: expecting preamble" and  "No connection could be made because the target machine actively refused it : IP #:port" (I'm using default port 80)

i'm novice in using this tool. pls have your say. Many thanks in advance.


Local Machine OS: Windows 7

Remote machine: Windows server 2008 R2 Standard (website(IIS 7) is hosted on

Build: dotTracePerformanceSetup.4.0.665.4

dotTrace: 4.0 Performance


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