nettracer

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2/7/2020

Windows 2012 R2 server fails to establish outbound connections

Hi there, It's been a very long while since I have blogged something here and it's time to come back...

Author: MuratKa1 Date: 01/11/2018

Testing Lync server 2013 external URLs from Lync clients (external web service, meet, office webapps, lyncdiscover and dialin)

Hi there, In this blog post, I’ll be talking about another powershell based tool which could...

Author: MuratKa1 Date: 05/21/2014

Testing Exchange EWS service accessibility from internal/external Lync clients

Hi there, In this blog post, I’ll be talking about a powershell based tool which could be used...

Author: MuratKa1 Date: 05/21/2014

How it works on the wire: IIS HTTP Client certificate authentication

I collaborated with a colleague recently where the IE client was failing to authenticate to IIS and...

Author: MuratKa1 Date: 12/30/2013

DNS SRV lookup from Powershell

[After posting this blog, I have realized that Powershell 3.0 already provides a built-in cmdlet...

Author: MuratKa1 Date: 10/13/2013

Testing STUN/TURN server connectivity from external networks through UDP 3478 by using Powershell

Hi there, While working on a Lync connectivity test tool, I developed a STUN/TURN server...

Author: MuratKa1 Date: 10/13/2013

External Lync 2013 clients cannot upload ppt or other files and whiteboard, poll, Q&A are greyed out on Lync client

Hi again, In this blog post, I want to talk about a Lync 2013 problem where external users fail to...

Author: MuratKa1 Date: 10/12/2013

Decrypting SSL/TLS sessions with Wireshark - Reloaded

Hi there, In a previous blog post of mine, I went through the steps of decrypting SSL/TLS traffic by...

Author: MuratKa1 Date: 10/12/2013

Running Lync 2013 WebApp plugin in locked down Terminal server environments

Hi there, In this blog post, I would like to talk about running Lync 2013 Webapp in Windows Terminal...

Author: MuratKa1 Date: 08/04/2013

Event ID 56417 may be logged on Lync server 2013 intermittently

Hi again, I dealt with a Lync server 2013 problem recently where the server was intermittently...

Author: MuratKa1 Date: 07/08/2013

Lync 2013 client may crash when Organization tab is clicked

Hi there, I was dealing with a Lync 2013 client crash problem a few months ago and I wanted to...

Author: MuratKa1 Date: 07/08/2013

Cumulative update version information for Lync client and Lync server

[Last updated on 27th February, 2014] Hi there, You can find a list of CU versions compiled from KB...

Author: MuratKa1 Date: 07/05/2013

Exchange integration error on HP4120 desktop phones - A CA trust issue

I would like to go through an integration problem between Lync phone edition devices and Exchange...

Author: MuratKa1 Date: 01/18/2013

Lync 2010 response group members phones keep ringing even if the remote party hangs up the phone

In this blog post, I’ll be talking about a response group problem where the response group...

Author: MuratKa1 Date: 01/18/2013

RDP connections might fail due to a problem with KB2621440 - MS12-020

I was helping a colleague who was dealing with a Remote desktop connection problem where Windows 8...

Author: MuratKa1 Date: 01/18/2013

I would like to talk about another Lync 2010 problem where desktop sharing was failing between two...

Author: MuratKa1 Date: 01/18/2013

Today I’ll be talking about a problem where the external Lync 2010 clients fail to sign in...

Author: MuratKa1 Date: 01/18/2013

SCCM client push installation may fail due to firewall problems

I was collaborating with a colleague of mine on a problem where SCCM client push installation was...

Author: MuratKa1 Date: 01/06/2013

TMG Safe search feature may not work as expected sometimes

In this post, I would like to talk about a TMG safe search problem which I dealt with recently. The...

Author: MuratKa1 Date: 01/06/2013

Slow performance when accessing a Sharepoint 2010 portal through an ISA 2006 array

I was involved in a slow Sharepoint portal access through an ISA 2006 array problem and I wanted to...

Author: MuratKa1 Date: 01/06/2013

Direct access client fails to connect to UAG DA server through IPHTTPS with various errors (0x800b0109 and 0x274c)

In this post, I want to talk about how I troubleshooted a direct access connectivity problem hoping...

Author: MuratKa1 Date: 01/06/2013

TCP delayed ACK combined with Nagle algorithm can badly impact communication performance

Recently I was involved in a network connectivity performance issue and wanted to share the root...

Author: MuratKa1 Date: 01/05/2013

Network trace analysis tricks III - How can I comment on packets in a network trace

After you get familiar with using protocol analysis tools like Network Monitor or Wireshark,...

Author: MuratKa1 Date: 07/11/2012

Network trace analysis tricks II - How can I focus on a certain packet range in a network trace?

In the second post of “network analysis tricks” series, I’ll explain how to focus...

Author: MuratKa1 Date: 06/27/2012

Network trace analysis tricks I - How can I see all TCP connection attempts in a network trace?

In the “network analysis tricks” series of posts, I’ll try to explain some...

Author: MuratKa1 Date: 06/22/2012

Network traffic capturing hints

In this post, I would like to talk about some important points about network capturing. If a network...

Author: MuratKa1 Date: 06/22/2012

When do we need to collect network traces?

Many Microsoft support engineers dealing with customer technical issues ask for network traces to...

Author: MuratKa1 Date: 06/22/2012

HTTPS access through TMG fails from a certain VLAN with a very unusual error: FWX_E_SEQ_ACK_MISMATCH

In this blog post, I’ll be talking about an interesting problem that I dealt with recently....

Author: MuratKa1 Date: 06/15/2012

Outlook anywhere (RPC over HTTPS) access to Exchange 2010 server via TMG 2010 fails after some time

In this blog post, I’ll be discussing an Exchange 2010 publishing on TMG 2010 issue. The...

Author: MuratKa1 Date: 06/12/2012

Getting HTTP 500 Internal server error when accessing a published web site through ISA 2004

In this post, I’ll be talking about a web publishing problem and how I dealt with it. The...

Author: MuratKa1 Date: 05/23/2012

Outlook MAPI connection to Exchange 2010 CAS fails through UAG 2010 direct access tunnel

In a recent case, I dealt with an Outlook MAPI connection failure problem through direct access...

Author: MuratKa1 Date: 05/22/2012

PDF file corrupted when downloaded through TMG server

Recently I dealt with a problem where PDF file downloaded from a certain external web site was...

Author: MuratKa1 Date: 05/21/2012

Internet Explorer doesn't display ISA or TMG error message 502 when connecting to HTTPS servers

Hi there, I would like to talk about an issue that I have dealt with recently regarding Internet...

Author: MuratKa1 Date: 09/22/2011

TMG initiates active FTP connections to external servers even though it's configured for passive FTP - a problem with FTP over HTTP

Hi there, In this blog post, I’ll be talking about another TMG problem where FTP over HTTP was...

Author: MuratKa1 Date: 09/21/2011

Java applications and TMG access rules that require authentication

Hi there, In this blog post, I’ll be talking about a TMG related issue. Actually it’s...

Author: MuratKa1 Date: 09/21/2011

Anatomy of a DoS attack that exploits WebDAV vulnerability in Apache Web server

Hi there, It has been sometime since I haven’t posted anything at the blog and finally got a...

Author: MuratKa1 Date: 09/08/2011

How it works under the hood: A closer look at TCPIP and Winsock ETL tracing on Windows 7 and Windows 2008 R2 with an example

Hi there, In this blog post, I would like to talk about TCPIP, Winsock ETL tracing a bit with an...

Author: MuratKa1 Date: 10/06/2010

SCCM packages may be distributed slower than standard file copy (xcopy/Windows Explorer)

Hi there, In this post, I’m going to mention about another issue where I helped a colleague of...

Author: MuratKa1 Date: 10/05/2010

SQL Browser may not be reachable through firewalls when it runs on a cluster

Hi there, In this blog post, I would like to talk about a problem in which I was involved as a...

Author: MuratKa1 Date: 10/05/2010

Bogus IP packets and Wireshark

Hi there, In today’s blog post, I’m going to talk about an issue that I have come across...

Author: MuratKa1 Date: 10/05/2010

How to decrypt an SSL or TLS session by using Wireshark

[Updated on 26th October 2013] The following blog post is the newer version of this blog post:...

Author: MuratKa1 Date: 10/01/2010

Why are local resources accessed slowly when loopback or local IP address is used whereas accessing the same resources over the network works fine?

Hi there, In today’s blog post, I’m going to talk about a local resource access...

Author: MuratKa1 Date: 08/16/2010

Effects of incorrect QoS policies: A story behind a slow file copy...

Hi there, In this blog post, I’ll talk about another network trace analysis scenario. The...

Author: MuratKa1 Date: 08/11/2010

Hi there, In today’s blog post, I’m going to talk about some registry keys that were...

Author: MuratKa1 Date: 08/11/2010

Does sqllogship.exe have anything to do with web servers in the internet? Story behind CRL check for certificates ...

Hi there, In today’s blog post I’m going to talk about a network trace analysis scenario...

Author: MuratKa1 Date: 08/09/2010

Where are my packets? Analyzing a packet drop issue...

One of the most common reasons for network connectivity or performance problems is packet drop. In...

Author: MuratKa1 Date: 08/06/2010

Is it real or Matrix? Some facts about network traces...

Hi there, In this blog post, I would like to talk about some facts about network traces. A while ago...

Author: MuratKa1 Date: 08/05/2010

Excessive ARP requests, is it malware or legitimate activity?

Hi there, In this blog post, I would like to talk about a network trace analysis scenario where we...

Author: MuratKa1 Date: 08/05/2010

Why does it take too long to retrieve data from SQL server over a WAN connection?

Hi there, In today’s blog post, I’m going to talk about how to troubleshoot a WAN...

Author: MuratKa1 Date: 08/05/2010

Exchange servers send ICMP and UDP packets to clients or Domain Controllers, why?

Hi, I would like to talk about a few network trace analysis cases where we were requested to find...

Author: MuratKa1 Date: 08/04/2010