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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Hello Experts,

One of my customers is running into an issue where they are unable to mount a mailbox in Exchange 2016 that was disabled by mistake and then reconnected to another user in AD.


Mary Doe's mailbox was disabled for some reason, and the help desk team, instead of reconnecting the disabled mailbox, they provisioned a new mailbox for this user. Once the user check the emails, obviously all email is gone because is displaying only items from this new mailbox.

Company has a test account named John Doe with a mailbox. The mailbox for John's account was disabled, and then following cmdlet was performed to reconnect Mary's original disabled mailbox to John's mailbox

Connect-Mailbox -Identity "Mary Doe" -Database DB100 -User "John Doe"

And the following error was displayed:

The LegacyDN xxxxx is in use by the following user in Active directory: Mary Doe. The value for LegacyD must be unique to each user.

In order to resolve the issue above, they added an extra blank space to LegacyDN attribute in AD for Mary Doe using ADSI edit tool, then ran cmdlet below, and Mary's disabled mailbox was successfully reconnected to John's account

Connect-Mailbox -Identity "Mary Doe" -Database DB100 -User "John Doe" -AllowLegacyDNMismatch

So, we also granted full mailbox permission access to Mary's and John accounts to perform troubleshooting, however we are unable to mount or open Mary's mailbox from John's account using outlook and OWA. Getting …
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I created a test exchange server 2016 (internal only) but Autodiscover is not working.
I tried troubleshooting but was unsuccessful.
please advice.
My client has an HP ProLiant DL160 Gen9 that has started rebooting randomly over the last two weeks, below is the latest bluescreenview which points to ntoskrnl.exe as the culprit however i have no idea where to start troubleshooting.

All applicable windows server updates installed and i also ran a system file check which did resolve some issues however the reboots still occur.

Any thoughts??

SBS2011 getting ready to replace the server, in the meantime DNS resolution is horrible however I'm not convinced it's the server I think it's on the ISP side. When I ping either DNS server from the ISP it has a lag well above 25ms to 35ms. This is not enough though to determine why DNS resolution is so slow and the reason for this post. How to proceed troubleshooting in this case.

SBS2011 doesn't use forwarders but I tried them anyway without any luck. I also added for testing purposes and nothing changed. SBS2011 DNS/DHCP is configure, without forwarders and is using root hints. Firewall is using DNS from the ISP.

Something strange, when I make a VPN connection my resolution is fine. I may not be fully understanding DNS through a VPN connection, my understanding is I'm routed through the server so shouldn't I see the same issues? Note, I'm not using SBS routing and remote access using L2TP on the firewall. Maybe I just answers my question and I'm routing around the SBS2011 Server.

Also upgrade the bandwidth which is nice, much faster but the DNS resolution is still extremely slow and an issue.
I have an NEC DT700 series phone. I think specifically it is a DT730.

Right now the message light is blinking, but the voice mailbox is empty.  It also has "MSG >>>" on the screen.

There is "Frontdesk" as the identifier, but I cannot clear that off.
I am having issues with my DHCP server having BAD_ADDRESS entries for a large number of addresses.  The Unique ID ends to be the reverse of the IP address in hex form. I have Conflict detection attempts set to 2.  It is only happening on the Scope attached to the secured wireless.  It seems to be about one bad address per minute or so. I've looked at the event logs on that server that I can find and there aren't any that match the time for the Lease.  Any troubleshooting tips?
I am updating a Windows 10 machine from 1607 to 1803. I continuously get the following error:

Windows update could not be installed because of error 2147942487 "The parameter is incorrect." (Command line: ""C:\windows\system32\wusa.exe"

I have run through the standard troubleshooting fixes listed here:

Any suggestions?
I am looking to prepare a template for cisco networking troubleshooting guide. Can someone help and share their layer1 through layer 7 troubleshooting guide or commands or any templates with details. Thank you.
there is 3 static ips on our network that need to be reserved for another device.  when I do a network scan mac address is: 00-01-45-03-ED-B9


Any ideas what type of devices could be?  Is there any other troubleshooting I can take besides looking at every device on the netowork?
each time when I log off and log back on to my virtual desktop  , my outlook signature goes away.

after troubleshooting I see in my signature folder thumbs.db is missing

anything you can suggest
Managing Security & Risk at the Speed of Business
Managing Security & Risk at the Speed of Business

Gartner Research VP, Neil McDonald & AlgoSec CTO, Prof. Avishai Wool, discuss the business-driven approach to automated security policy management, its benefits and how to align security policy management with business processes to address today's security challenges.


I want to create a trigger on a table on INSERT. So when an INSERT attempts to happen on the table, a SELECT is first run and if the SELECT returns rows, the INSERT is cancelled but the transaction ls logged to another table.

The code that has the SELECT in, is as follows


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The above works as expected.

I'm now trying to develop a trigger on the table in question:

/****** Object:  Trigger [dbo].[TRIG_WIDGET_ADDITIONAL_COUPON_ISSUE]    Script Date: 08/16/2018 09:41:50 ******/

	DECLARE @inserted TABLE ([couponID] [bigint] NOT NULL,[organizationID] [bigint] NOT NULL, [orgLevelID] [bigint] NULL, [couponTypeID] [bigint] NULL, [accountID] [bigint] NULL,	[promotionID] [bigint] NULL,[customerID] [bigint] NULL,[hashCode] [int] NULL,[couponCode] [nvarchar](32) NULL DEFAULT ((0)),[serialNumber] [nvarchar](50) NOT NULL,[createdLocalDateTime] [datetime] NOT NULL,[createdHostDateTime] [datetime] NOT NULL,[createdLocationID] [int] NULL,[issuedLocalDateTime] [datetime] 

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I am trying to automate my keep alive on my router WAN side. I just want to monitor the provider router interface.. Will the IP SLA do the trick (see below)? How do I apply it to the interface? My router is a Cisco 2911 and it does not have the ip sla # command.

ip sla 10
icmp-echo source-ip
frequency 300
timeout 3000

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Windows Server 2012R2

XPS Document writer was removed from the 'Devices and Printers'

While troubleshooting the Feature was also disabled using: Dism /online /Disable-Feature /FeatureName:Printing-XPSServices-Features

I am now unable to 'Enable' the feature. "DISM failed. No operation was performed." (log is attached.)

Step 1. I'd like to get the Feature enabled.
Step 2. I'd like to get the XPS Document writer back to the 'Devices and Printers'

I have scoured about 20 blogs already; everything on this site, Quickbook links, scf scans, Sharing other XPS printers, deleting drivers, copying drivers, windows updates, add/remove Office365, DISM scans.
I am running VMware ESXi 6.5u1 hosted by OVH.

This morning i receioved an email indicating my server had stopped responding and a hard reboot was completed. Non of my websites had come online so I logged into the ESXi console. I noted that the hosts had not restarted.

I restarted the hosts and also enabled Autostart. Both of the guests restarted and were responding. However a couple of minutes later the ESXi server and guests again stopped responding.

I have again restarted the server and now it does not  boot to ESXi console at all. It does not respond to pings and apparently is not working.

I presume that it is the guests starting that is causing the server to stop responding.

I can boot the server into the OVH recovery image and access the server using telnet. However the recovery web console is not available.

Can someone assist in troubleshooting this. The first thing that I think should be done is to disable the autostart on the guests. Can this be done through editing a file from recovery?



So I am trying to troubleshoot replication issues in this domain with two domain controllers DC1(PDC), DC2(BDC). About a year ago the PDC stopped working and they were having issues with users logging, changing passwords and stuff so they promoted DC2(BDC). Upon inspecting today I found that the replication issues were caused due to netlogon service not running and every time a manual replication was tired "The target principal name is incorrect" as an error was thrown.

So after some troubleshooting the netlogon service is running now without any issues but now I am get the following error when I try manual replication.

The following error occurred during the attempt to syncronize naming context CN=Configuration,DC=Domain,DC=Local from Domain Controller AD to Domain Controller AD2; The directory service cannot replicate with this server because the time since the last replication with this server has exceeded the tombstone lifetime. This operation will not continue.

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Also when I run the "netdom query fsmo" command both server claim to be owner of all roles except for DC2 not claiming Domain Naming Master Role.

netdom query fsmo on DC2
Schema master     
Domain naming master
RID pool manager  
Infrastructure master
The command completed successfully.

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netdom query fsmo on DC1
Schema master     
Domain naming master
RID pool manager  
Infrastructure master
The command completed successfully.

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Can you please tell me what's the best solution here for me?

Thanks so much!
Outlook not updating address book. If I try download the offline address book in Outlook, it gets stuck on connecting to Microsoft Exchange.

2 x Domain Controllers - Replicating to each other
1 x Exchange Server 2013 Standard CU21

Troubleshooting steps performed so far.

1.) Checked OAB Virtual Directories, both internal and external directories are pointing to the correct URL's but the OAB database hasn't updated for a few months now
2.) Run Get-OfflineAddressBook, shows the OAB as "DGE-Default <Ex2012>" and that it is a Version 4
3.) When I run the checks on the Arbitration mailbox, the Arbitration / System Mailbox cant be found.
4.) If I check in Active Directory all the System Mailboxes are missing.

I then moved on to troubleshooting the Arbitration mailbox and see if i could re-add them using the Exchange  setup.exe /PrepareAD as per a Microsoft Technet article.
This passes the prerequisites but fails when looking for the Default Email Address Policy

The operation couldn't be performed because object 'Default Policy' couldn't be found on 'serverXXXX.local'

Attached a copy of the Exchange Setup logs.

When running Get-EmailAddressPolicy I can see the 3 policies that are set up on the server but not the Default Policy.
If I run Get-EmailAddressPolicy -IncludeMailboxSettingOnlyPolicy then I can see the Default Policy as it has no email address properties attached to it.

I can't seem to find a way to add email address …
I have a Windows Server 2012 that freezes and eventually just goes to black screen.  What tools are there for me to fix this server?
Where can I start to troubleshooting this server?
Since installing multiple windows updates on an SBS 20008 server  the default company web is unavailable as users are presented with the page HTTP 404 page not found, i have gone through various troubleshooting steps including IIS reset but still unable to resolve.

Any ideas?
Hi EE,

I am trying to install a windows update on my Server KB919355 x64, I am getting error message update is not applicable to this computer. I have checked via PowerShell the KB hasn't been applied how do I fix this?

Download link

I also tried to install this via windows update but the server is in a locked down area of the network and network admin sick until Monday at least.

Any help is appreciated.

Thank you.
10 Tips to Protect Your Business from Ransomware
10 Tips to Protect Your Business from Ransomware

Did you know that ransomware is the most widespread, destructive malware in the world today? It accounts for 39% of all security breaches, with ransomware gangsters projected to make $11.5B in profits from online extortion by 2019.

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 …
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!
Exchange 2010 SP3(single server)
Couple days ago Exchange stoped sending mails.
If I restart server everything is fine.
Troubleshooting the issue I found that my colleague updated server and installed NET framework 4.7.2.
I presume net framework is problem
What is the best way to uninstall net framework 4.7.2?
Exchange 2010 stops sending and receiving messages after 8-9 hours. Suddenly, like 5 days ago, problem occured first time. I do not know where to start troubleshooting. After restart everything is OK for another 8-9 hours. Antivirus (ESET) uninstalled, but problem remains. Exchange 2010 with latest updates (updates were installed after problem appeared). OS W2008 with latest updates (automatic).

No error in event log seems to be clear and indicating any problem. Please advice where and how to start?

many 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.



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.