Troubleshooting is a problem-solving process of evaluating faults that occur in a mechanical or electronic system. Steps often include recreating the problem and then trying alternative and creative solutions in order to fix the situation. Troubleshooting is deployed when software or hardware are rendering abnormal responses or remain unresponsive.

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Plan to purchase a network troubleshooting tool. This tool is one of the more popular brands on the market. It is the inline version. Our company is  using a Cisco switch network environment. Our switches are configured for port security using “Sticky Macs” with a maximum of 2 addresses allowed. One for computers and the second for IP phones.

My question is are these inline testers useful or useless in a Cisco port security network. I have been told that these type testers have MAC addresses that will “trip” port security  and render the tester virtually useless. My main purpose for inquiring about this tester is when I attempt to trace cables runs to identify and display what interface the cable is connected to on the switch.

Also, another issue is, that because some of these switch are configured with port security and ACL list, the port under investigation may be  “ shut down or inactive”. Will this popular network tester indentify and locate interfaces on the switch that are INACTIVE?
The cable run from the patch panel to the switches in out closets are a complete mess!
It looks like a giant plate of spaghetti!!! I am quite sure you know what I am talking about!
As a result it is very difficult to trace the Ethernet patch cable “all the way” to the end point on the switch panel. Most times I have to take an educated guess when trying “see” where exactly the cable goes into the interface.

And finally, is there a network tool on the market that will,do what I …
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I need help troubleshooting a firestore query into array.
Hello. I am troubleshooting a WYSE Thin Client with Win Embedded Standard 7.  Earlier yesterday, I got the error" Failed to Connect to MQTT Server! twice. I'm stumped at the moment as to why that is happening. It isn't affecting the home user to where she can't log into RDP, etc, I simply want to know how I can rectify this error from coming up in my Events tab on the Wyse Management Suite. Thanks!
I have one user (out of 60) whose Sprint phone randomly but often keeps getting the message pop-up: "The SIM card has locked. Please power cycle the device and if the problem persists contact customer service." This was a new Samsung S9. After useless troubleshooting with Sprint tech, we returned the phone for a replacement. After a few days the issue appeared on the new phone as well.
Any suggestions would be appreciated. This is not happening to nay of our other users.


I have a server running Windows Server 2008 SP2 32bit

I was attempting to perform Windows Updates today which were immediately failing.. In an troubleshooting effort, I attempted to restart the trustedinstaller.exe service, which immediately rebooted the server and it has been stuck in an "Failure configuring Windows Updates, Reverting Changes, Do not turn off your computer" state which just reboots the server and continues in a loop..

I have done some research on this and performed the common fix for this, from what I've seen: Boot from startup disk, enter the command line and rename the C:\Windows\SoftwareDistribution folder to SoftwareDistributionOLD and rename C:\Windows\winsxs\pending.xml to pending-xml.OLD

However, this solution that appears to work for most people doesn't work for me.. I'm at a loss as to what to do. There are no system resource points, startup repair doesn't work.. Please help.
Hello. I am troubleshooting a WYSE Thin Client with Win Embedded Standard 7.  Earlier yesterday, I got the error" Failed to Connect to MQTT Server! twice. I'm stumped at the moment as to why that is happening. It isn't affecting the home user to where she can't log into RDP, etc, I simply want to know how I can rectify this error from coming up in my Events tab on the Wyse Management Suite. Thanks!

Any can advice how to troubleshooting the .vmdk vdisk missing and corrupted? see attached error screenshot.

Use VMware Converter, to create a V2V, or right click and use CLONE to CLONE the VM are failed. Restored from backup also failed


I'm experiencing some issues in out Office 365 Hybrid environment...

Strangely, out of the few thousand users, there is a very small handful of users that people who have mailboxes in O365 get the following NDR when emailing them.

Sender:       (mailbox in O365)
Recipient:   (Mailbox On Premises - rejected your message to the following e-mail addresses: gave this error:
Hop count exceeded - possible mail loop ATTR1 []
A problem occurred during the delivery of this message. Please try to resend the message later.

Diagnostic information for administrators:
Generating server: #554 5.4.14 Hop count exceeded - possible mail loop ATTR1 [] ##rfc822;

Recipient does have an email alias on-prem of but doesnt have a Target Address stamped. So I would think it wouldn't be sending the message back to ExOL etc.

I don't know where to start troubleshooting, this is only happening when cloud users try emailing …
I have a 10Gbps Direct Connect circuit from our enterprise data center to AWS. Each VPC has a different
sub-interface and different BGP peer. See snippet below. What's happening is that ping tests to some BGP
peers might have NO loss be other BGP peers are seeing 2 to 10% packet loss from the perspective
of our monitoring system in the data center. If I look at the Ethernet port or the PortChannel port there
are no incrementing errors nor discards that I can see. If I try to show anything about the subinterface
(say show interface port-channel3.1002) - error information is not available. I'm not sure how I can
look at the interface of the router on the AWS side of the connection.

My question: how can I go about troubleshooting the ping loss to these sub-interfaces/bgp peer addresses?

inherit peer aws-dx-peering
description peering to preprod

inherit peer aws-dx-peering
description peering to prod

interface port-channel3.1001
  description DX for preprod
  encapsulation dot1q 1001
  bfd interval 300 min_rx 300 multiplier 3
  no ip redirects
  ip address
  ip router ospf 1 area

interface port-channel3.1002
  description DX for prod
  encapsulation dot1q 1002
  bfd interval 300 min_rx 300 multiplier 3
  no ip redirects
  ip address
ip router ospf 1 area
I have been having an issue with Azure AD Connect and have run out of troubleshooting ideas and hoping someone can help. I have a support ticket open with our Office 365 re-seller but so far they have been unwilling to open a ticket with Microsoft.

The issue is that our password hash synchronization stops working after a few days. The event viewer logs an event 611, Password hash synchronization failed for domain: (our domain name). Details:
Microsoft.Online.PasswordSynchronization.SynchronizationManagerException: Unable to open connection to domain: (our domain name). Error: Unable to retrieve source domain information. ---> Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsException: Unable to retrieve source domain information. ---> System.DirectoryServices.DirectoryServicesCOMException: There is no such object on the server.

I originally uninstalled and reinstalled Azure AD Connect and that fixed the problem for a few days. Then the same error re-occurred. I originally thought that it might have been a networking issue with our Hyper-V cluster because disabling IP-Sec offloading on the VM and rebooting the VM caused the password synchronization to start working. However, I think that was just a coincidence because the password hash failed again a day later and doing the same thing had no effect the second time around. Either way, the support agent I have been working with wanted me to install the Azure AD Connect on a physical computer, …
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When i move this user mailbox from db1 to db4 which encountered this error:

Property expression ‘user1’ isn’t valid values are: Strings that includes @, cannot be the last character


1. Checked user at AD and confirmed no space and invalid character
2. Checked ADSI Edit > OU=OP > OU=Mail > CN=user1 no invlid character
3. Checked user can login to the outlook and OWA without any issue like file corruption

How to troubleshooting and can move user mailbox without this issue.

If need to run powershell, can i understand where to run it and what will be the easy command for me that never used powershell. Run In exchange 2010 or PC with Powershell login with import-module.  


Encountered this outlook connecting message (hang for while) when opening this email user with signature logo of website link. see attachment.

Performed the following troubleshooting.

1. Uncheck all security trusted settings in outlook
2. add in * with 2 or 3 value to allow internet site
Power outage created a mess with Exchange and auto discovery issues since. After power outage cycled on a 2012 Sever Standard with two VM's, 1. PDC 2. Exchange. After server came up Exchange doesn't allow auto-discover and Outlook clients don't connect. First problem was noticed when all Outlook clients reported "Trying to connect" to the Exchange server. For troubleshooting purposes I deleted an Outlook profile and get the following trying to create a new profile.
errorerror2Some certs were replaced and we believe the problem may be here, we're looking at certs and will follow up. Another interesting issue is the IP address on the exchange server was hardcoded before the server restart. However after the power outage when the server restarts in DNS and the "Network" tab on the VM show a different IP address, it's dynamic rather than the static. Tried to get things working with the static IP however Exchange will not work at all this way. Changed the static IP address on the Exchange server to DHCP and it works with OWA only. Outlook clients still won't connect. With auto-discovery not working all phones have disconnected, this likely will change after auto-discover is working again.
Currently Troubleshooting an issue on our file server with a large share where I as an admin via any commputer am unable to copy or save changes to the share.

Will having the read only check box affect users from copying or making changes to files\folder  in the sub folders on a network share? Event though Ntfs permissions and share permissions have been set accordingly.

Hello Experts

I am searching for emails in Outlook 2010 from Access 2010 VBA and want to use the AdvancedSearch method.
I know that the email I am searching for exists because I can see it in the Deleted Items folder. However, after at least 30 minutes of searching, AdvancedSearch hasn’t yet found it. The AdvancedSearchComplete event hasn’t yet fired (or if it has I haven’t detected it) and the search result set is empty. After this time, I find it hard to believe that sheer slowness is the problem.
Some more details:

1.      All the action is occurring in the Access class module for my email management form. In the form’s module header, I declare a WithEvents reference to my desktop Outlook instance, which I check is up and running, along with some related stuff:
Private WithEvents molApp As Outlook.Application      ‘ in class module header
Private mblnIsSearchComplete As Boolean   ' set True when email search completes

Private molNS As Outlook.NameSpace
Private molFldrBase As Outlook.Folder
Private WithEvents molFldrInbox As Outlook.Folder
Private WithEvents molFldrDeleted As Outlook.Folder
Private WithEvents molInboxItems As Outlook.Items

2.      In the Form_Open event handler, I set up the necessary references, first to Outlook, which I check is up and running, and then to key email folders:
  Set molApp = GetObject(, "Outlook.Application")  ' will raise error if not already running
   mblnIsSearchComplete = False

   Set molNS = …
I am trying to provide access to a camera on a remote network for a user by configuring VLAN on various L3 HP switches. The network I am working in has numerous VLANs and the path from the device to the camera crosses at least 4 L3 switches. I have been unable to get the connection to work and at this point need troubleshooting tips and a better understanding of how this should work.

At this point I would like to focus on a suggested methodology to troubleshoot connectivity on a VLAN. I have been told ping will not work because this is a L2 VLAN not intended to be routed from everything and that is why ping will not work, I think this is nonsense but please let me know if there is a way to track the VLAN path to see where the disconnect might be. Also, there has to be a L3 component as the source and destination networks are different and the route to the destination is specified on an L3 route table.

The following is the basic configuration:

Device :
Attaches to Switch 1 in VLAN 13 using an untagged (access) port. The PVID (native) VLAN on the configured port is 13.
There is no VLAN 13 interface configured on Switch 1. Using NDP and routing tables, I know that Switch 1 connects to Switch 2 using Tagged (Trunk) ports that include VLAN 13.
Switch 2 does not have an interface configured for VLAN 13.
I am unable to ping the camera from Switch 1 or Switch 2. There are no ARP entries for VLAN 13 in Switch 1. There are VLAN 13 entries in the ARP table on Switch …
new to certificate troubleshooting but getting this error on my AD server

also does this mean this AD server is also a certificate server?

its a Win 2008 R2 Std
I had this question after viewing STOP: c0000218 (Registry File Failure) - Windows 2000 Server.

Hello everyone...after consulting with a few other forums on this topic, with limited success, I am hoping to find a definitive solution here on the Experts Exchange.

Having posted a number of topics on this issue elsewhere, I'll keep it brief: I have an HP Vectra desktop computer that runs Windows 2000 Professional, but the device was stricken with the c0000218 "Blue Screen Of Death" back in 2010. With the help of some online computer-repair forum users elsewhere, I've managed to make some progress in trying to troubleshoot the error In the past year-plus, but have unfortunately hit a bit of a standstill in the process, and no other forum users have been able to help me move forward. Which finally brings me here to the Experts Exchange page. To save some trouble, I will provide links to the other forum topics I've started, some of which have screen captures to illustrate my progress, at the bottom of this post.

Fortunately, much of the hard work has already been done by myself with the help of the other forums' users, so hopefully, that one helpful tip to get through my logjam can come from any one of you here on this site.

Thanks in advance for any helpful replies :-)

Microsoft Answers
Bleeping Computer [1] [2]
CNET Forums
Backstory:  I did not configure this.  This configuration was already in place for the most part.  The only thing I changed was the priority queue percentages.  The markings were already in place.

The issue here is that when I do packet captures in Wireshark,  I don't see any of the marking

This is the QoS configuration on a 2811 Cisco router:

class-map match-any SDM-Transactional-1
 match dscp af21
 match dscp af22
 match dscp af23
class-map match-any SDM-Signaling-1
 match dscp cs3
 match dscp af31
 match dscp cs2
class-map match-any SDM-Routing-1
 match dscp cs6
class-map match-any SDM-Voice-1
 match dscp ef
 match dscp af43
 match access-group 180
policy-map SDM-QoS-Policy-1
 class SDM-Voice-1
  priority percent 60
 class SDM-Signaling-1
  bandwidth percent 15
 class SDM-Routing-1
  bandwidth percent 15
 class SDM-Transactional-1
  bandwidth percent 5
 class class-default
policy-map SDM-QoS-Policy-3
 class class-default
  shape average 9000000
   service-policy SDM-QoS-Policy-1
policy-map SDM-QoS-Policy-2
 class class-default
  shape average 2944000
   service-policy SDM-QoS-Policy-1

interface Multilink1
 description CenturyLink MPLS -
 ip address x.x.x.x x.x.x.x
 ppp multilink
 ppp multilink interleave
 ppp multilink group 1
 service-policy output SDM-QoS-Policy-2

interface GigabitEthernet0/1
 description Spectrum/Brighthouse Cable
 bandwidth 3072
 ip address x.x.x.x x.x.x.x
 ip …


Troubleshooting is a problem-solving process of evaluating faults that occur in a mechanical or electronic system. Steps often include recreating the problem and then trying alternative and creative solutions in order to fix the situation. Troubleshooting is deployed when software or hardware are rendering abnormal responses or remain unresponsive.