Thousands of 4776 events - printing

I'm facing a problem which causing thousands of successful 4776 events on DCs. I figured out that some kind of network printer enumeration causing it. Every refreshing or opening printers in word for example, triggers a lot of 4776. It takes place even when user doesn't use computer so it is locked. Any idea why it works like that? I suspect that it is caused by opening printer named pipe, I see in ProcMon create, close file on pipe\spools printer path. Server is W2K8 R2 , client W10
Thanks in advance

This problem "Thousands of 4776 events" usually occurs every time that a credential validation occurs using NTLM authentication. It shows successful and unsuccessful credential validation attempts.
Only for the authoritative accounts this error occurs. For domain
accounts, the domain controller is authoritative. For local accounts,
the local computer is authoritative. This event also generates when a workstation unlock event occurs.
Obtain the source workstation address from 4776 event log and please check below steps:
Try checking whether the user is entering wrong credentials to run scheduled tasks, start services etc.
Try checking the credential management to know if there are any old credentials present in cache.
While mounting the network disk check whether you have entered wrong password.
Check if there are any third-party programs that cache the user's wrong password.
References:
4776(S, F) The computer attempted to validate the credentials for an account. (Windows 10) - Windows security | Microsoft Docs.
Event ID 4776 / 0xc00006a - Microsoft Q&A.

Related

Server timeout and sftp timeout. What to do?

Since 12h the website (Wordpress website) that is hosted on Google Cloud Platform has a time out issue. After 60 seconds of trying to load the website, the following message appears "The connection has timed out".
When trying to connect with SFTP, same issue.
What should I do to resolve this?
Since two different services stopped to work at the same time it
sounds like a networking issue. There is a timeout, therefore there is the server not answering at all to the requests.
What to do?
I would proceed with this general troubleshooting steps, if you want you can upload your question with the result of these commands/question to proceed with the troubleshooting.
First of all I would check if you are able to ping the
external/public IP of the instance.
I would check if the firewall rules allows TCP80/TCP443 and TCP22, Notice that on GCP you need to create the rule and assign the TAG to the machine from its detail page if the the rule does not apply to the whole network.
Are you able to ssh into the instance?
I would check if the processes are actually listening netstat -tuplen
If you are able when logged into the machine do you have access to the internet? Are you able to ping external IP? If not whats about internal IP?
I would go to the "activity" page of your Google Cloud Console to check which actions have been taken while the instance was still running.
I would check as well the history of the Linux machine to check if you run some commands acting on the network configuration of the machine.
Note that if you cannot SSH into the machine you can always access through serial console setting a password for your username through a startup script.
UPDATE
I had the possibility to take a look into the project, the machine was stopped due to issue with the billing account (it was closed) after the free trial period ended.
I would suggest you to go again trough the documentation regarding the upgrade of the billing account
If you have still some doubts or question after you perform this operations you can file a case at this link with the billing team and they will help you to solve the issue.

TF246017: team foundation server could not connect to the database

I am facing a problem with logging into TFS. I get the following error:
Exception Message: TF246017: Team Foundation Server could not connect
to the database. Verify that the server that is hosting the database
is operational, and that network problems are not blocking
communication with the server. (type SoapException)SoapException
Details:
Hi the below steps worked for me.
Select Application Tier in the TFS Administration Console.
In the Application Tier Summary which contains the Service Account details.
Click Reapply Account.
I know this is old, but here was my situation:
We have 11 collections on our instance, 2 were failing with this error, showing me it wasn't an access / connection issue. Checking Event Viewer (as #Andy Li-MSFT suggests) showed it was
A timeout occurred while waiting for memory resources to execute the query in resource pool 'default' (2). Rerun the query.
Checking task manager showed the culprit - elastic search was using well over 2GB of memory. I killed the service, the collections applied the patch quickly without issue.
Looks like I need to ask our server admins to give us a bit more memory....
Please check below thing to narrow down the issue:
Make sure you are the member of the Administration Console Users.
Otherwise you cannot access the Admin Console.
Make sure the SQL Server is stated and available, and the network
connectivity is OK.
Check the Service Account, make sure the Service Account has been added in
SQL Server.
You can also refer to the solution in below link to fix the issue:
https://www.ganshani.com/alm/tfs/visual%20studio/solved-tf246017-team-foundation-server-could-not-connect-to-the-database/
If above solution can not resolve the problem, please check the Event log. The Windows Event Log is a good candidate where to look for the potential cause.
For me I've solved the issue by changing the recovery mode Simple -> Full in the database.
Please refer to: https://www.mssqltips.com/sqlservertutorial/3/sql-server-full-recovery-model/

Cannot open database requested by login

I have a SQL Server 2008 R2 Express database.
I have written a Delphi application that uses a TADOConnection object to connect to the database. It works just fine on my computer. It fails to connect from other computers on the network.
It gives the error message:
Cannot open database "PeopleNetLink" requested by the login.
I have found all sorts of questions about this error message. I have found none that used SQL Server authentication and worked on one computer and not on others.
My connection string is
Provider=SQLNCLI10.1;
Integrated Security="";
Persist Security Info=False;
User ID=PNetLink;
Initial Catalog=PeopleNetLink;
Data Source=W1CNVS02\SQLEXPRESSPAY12;
Use Procedure for Prepare=1;
Auto Translate=True;
Packet Size=4096;
Initial File Name="";
Use Encryption for Data=False;
Tag with column collation when possible=False;
MARS Connection=False;
DataTypeCompatibility=0;
Trust Server Certificate=False;
Server SPN=""
Further experimentation reveals that if I log on to another computer as an admin, the program will log in successfully. This tells me that it is not using the user ID specified in the connect string. Now the question is "why not?"
This is a bit of a long-shot, as I don't have Sql Server 2008 installed, only the 2014 version. And maybe you've tried this already, but I spent hours on this problem before I found the step I was missing.
Assuming a utility like MS's PortQry shows the server's local network firewall is open and that your edition of 2008 comes with a copy of Sql Server Management Studio installed:
Start SSMS on the server,
Right-click the Sql Server's Properties
In the Properties pop-up, click the Connections tab
Check the checkbox "Allow remote connections to this server."
In some Sql Server editions, "Allow remote connections ..." is not check by default, which seems to square with marc_s's comment.
Update: Regarding your added "This tells me that it is not using the user ID specified in the connect string.":
If you open the DFM as text and hand-edit the connection string so that the "User ID" has a completely bogus value, then go back to the connection string builder, you should find two things:
The Enter information to log on to server reverts to Use a specific user name and password, so if you then click Test connection, the test unsurprisingly fails.
If you then select Use Windows NT Integrated security and click Test connection again, the test succeeds.
From 2., it is evident that the "User ID" in the connection string is ignored when using Windows authentication. That doesn't seem surprising to me, since the point of using Windows authentication is that the credentials used are those of the logged-in Windows user. You've already established that if you log in on the other computer as an admin (I assume you mean a Windows administrator account), the connection succeeds, so I'd have thought that the non-admin account needs to be added to the Sql Server's recognised users if you're wanting to connect using that ID (though I confess it's not at all clear to me whether you're actually trying to connect using Windows authentication of a specific Sql Server account).
If you're still stuck try using e.g. the Microsoft OLE DB Driver for SQL Server instead of the SQL Server Native Client. You might also single-step through this article:
https://social.msdn.microsoft.com/Forums/en-US/523c7b7e-6216-4790-87cb-945f3c1f4c5e/can-not-connect-to-microsoft-sql-server-express-2012?forum=sqlexpress
Also, google
sql server express 2008 remote "secpol.msc"
and note articles such as this one
https://social.msdn.microsoft.com/forums/sqlserver/en-US/1f5221bf-f5c3-4307-836b-a4f9dc07f02f/very-strange-remote-connection-issues

Dealing with service dependencies that time out or fail

I have writen a windows service that overwrite Logon and Logoff methods of ISenesLogon2 to check out when logon and logoff occure and then insert the log information into the sql server on server computer.
But it has problem when i turn on the client computer just after the server.
In this situation my service could not insert in sql server.
I think it's because of that the sql server did not load completely before the winservice tried to access to it.
So i want to find a way to check programmatically if the sql server is ready and then try to work with?
Your service cant start until its dependencies remote or otherwise have also started. Checking SQL Server is easy, try and connect to it and retry until you succeed.
Only problem is services have timeouts on startup, you cant sit and repeat this indefinitely.
Things that cannot be reliably started in a reasonable timeframe should not be services or they should fail as soon as possible. Otherwise you will end up with a lot of support requests for your service timing out.
Services are also usually not interactive to the user, so the failure is worse because you cant directly tell the user that your not up unless you do a tray icon.

IIS7, SQL 2008 and ASP.NET MVC security

I have an ASP.NET MVC application that I'm working on. I've been developing it on Windows Server 2003 with IIS6 and SQL 2008 Express, and everything was working great. I recently decided to try out the Windows 7 beta, so now I'm using IIS7, and have run into a problem with connectivity to my database that I can't seem to figure out.
I can run/debug the app just fine, but whenever I try to access a page that needs to access the database, I get the following error:
"Cannot open database "MyDatabaseName" requested by the login. The login failed.
Login failed for user 'IIS APPPOOL\MyApplicationName'."
I've obviously got some security configuration setup incorrectly, but I can't seem to find any good documentation on how to set it up correctly. I've tried giving NETWORK SERVICE permissions on the database, but that didn't seem to work. Anyone know what I need to do to give "IIS APPPOOL\MyApplicationName" permissions to this database? Am I missing something obvious?
Thanks...
If you are NOT using Active Directory, then ignore all of the other solutions mentioned here. The confusion stems from the new ApplicationPoolIdentity setting default in IIS 7.5+ (MS keeps changing the identity mechianisms)
Open SQL Management Studio, connect to your local machine as an admin.
Expand the Security branch.
Right click on Logins and select New Login
Into the Login Name field, type "IIS APPPOOL\MyApplicationName". Do NOT click the search button. The user profile dosn't actually exist on the local machine, it's dynamically created on demand.
While you're looking at it, don't forget to add the user to a database or a server role.
The error means the web application doesn't have access to your database. On Windows 7 / IIS 7, by default each application pool has its own user. It seems the idea is to improve security by restricting what that web application can do (in case it gets compromised and controlled from the outside). You can change what user the application pool is running under but that will defeat its own purpose. A better way seems to give the pool's user the needed permissions (and not a bit more).
On the SQL Management Studio connect to the server you want your web app to connect (tested with SQL server 2008). Go to
Security -> Log ins
right click, New Log in. In the form that comes up leave everything as default except username, where you have to type whatever username the web app is trying to use, in this case 'IIS APPPOOL\MyApplicationName'. Note that the search function of that dialog fails to find or check as valid that user, but nevertheless it works.
Still on the SQL Management Studio connected to the server go to
Databases -> *YOUR-DATABASE* -> Security -> Users
right click and New User. I'm not sure if the user name field there has any effect, I just set it the last part of the username, like MyApplicationName. Then I've set the login name to IIS APPPOOL\MyApplicationName. You can click on the ... button and use the check and search, this time it works. If you don't do the previous step, the user will not be present here. Then give it whatever permissions you want to this user, like db_datareader.
And that's it, you've given permission. If lack of permissions was your problem, then it should be solved (or at least, I've just solved it that way).
I have a total amount of 2hs of experience with IIS and about three weeks with SQL Server and less than two months with Microsoft technologies so take my advice with a grain of salt, I can be totally wrong. (If another person can confirm these are the right steps, feel free to remove the last warning).
Here is an article that explains why AppPoolIdentities are in use; basically, it's about enhanced security: http://learn.iis.net/page.aspx/624/application-pool-identities/
(That article claims I can use these virtual accounts just like any regular account but on my Windows Server 2008 that does not seem to be possible; adding e.g. IIS AppPool\DefaultAppPool just produces an error: "The following object is not from a domain listed in the Select Location dialog box, and is therefore not valid.")
Erick Falsken is right, however he is missing the User Mappings. So right click on the new
IIS APPPOOL/DefaultAppPool, click on Properties and then check boxes for:
1) databases master and yourdatabase
2) db_owner and public
This error usually means that the user that your site is running as (or more to the point the application pool), does not have permissions to use the DB. You can either check in IIS what user the pool is running under and give them permissions, or instead change your SQL connection string to not use trusted authentication and supply the credentials of a user that does have permission in the connection string.
Edit:
If you right click on the pool Identity section and go to properties, it should come up with a box that lets you either choose from 3 builtin system accounts, or specify your own account. Either give one of the builtin accounts permission for the DB, or use an account that has permission. Or leave it as is and change your connection string.
Well...changing the ApplicationPoolIdentity property and setting it to NETWORK SERVICE seems to have fixed my problems. Not sure if that's the "right" way to do things or not (as in, I'm not sure if that's the recommended way to do things in IIS7 or not), but it seems to at least be working and has gotten me past this hang-up for now. Thanks.
I'm familiar with the idea of giving permissions to the user that the application is running under...my problem is that in IIS7, the "user" seems to be virtual or something strange like that. Prior to me changing the "Identity" property of the Application Pool properties to NETWORK SERVICE, it was set to "ApplicationPoolIdentity", and the error I was getting was that "IIS APPPOOL\MyApplicationName" didn't have access to the database. When I attempted to add the "IIS APPPOOL\MyApplicationName" user to the database, it didn't appear to exist...not that I could find anyway.
So my ultimate problem is not understanding or being able to find any good documentation on how the IIS7 security model works. When I created the application, it seemed to create an AppPool with the same name just for this application. I don't know exactly what changes I need to make to give the application and/or the user it runs under privileges to the database, considering the fact that the user that the AppPool runs as doesn't appear to actually exist.
As I mentioned, changing the Identity of the AppPool to NETWORK SERVICE seems to have worked for now, but I'm trying to find out what the best practice is for this kind of thing under IIS7. Thanks.
leave the hard problems for someone else -
create a sql user and use SQL Auth. :D
If you follow Mr. Fernández' advice, you will get everything working. This is the new way of giving least privilege to a site.
So don't do the easy, less secure thing (NETWORK SERVICE). Do the right thing. Scroll up. ;)
Using Trusted Connection in Windows Authenticated Mode:
OS: windows 7 32 bit
IIS 7, Sql Server 2008 R2 Express
Connection String:
cn.open "Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=test;Data Source=mycomputername\sqlexpress;" (if instance name is sqlexpress or whatever instance name you have used)
If you are not able to connect sql server using windows mode authenticated connection to sql server 2008.
NT AUTHORITY\IUSR Account might not have permission in sql server to authorize connection with database.
Connect Sql server using windows authentication mode.
Expand Security node.
Select NT AUTHORITY\IUSR (IF NOT THERE THEN ADD NEW LOG IN FOR THAT)
Click on "User Mapping" under Select a page at Log-in properties window.
Select the database that you are trying to connect.
Select following permissions from "Database role membership for:......"
1. db_datareader 'this allows to open connection
2. db_datawriter 'this allows to fetch data records from datatable
The first step is to verify which account your website is running under. Create a simple aspx page with:
<%# Page Language="C#" %>
<% Response.Write(System.Security.Principal.WindowsIdentity.GetCurrent().Name); %>
If you're using windows authentication the WindowsIdentity account will need to have a login in your SQL Server. Under Security -> Logins -> Login New you'll want to add whatever name that was displayed by WindowsIdentity and make sure Windows authentication is selected.
If you ever happen to move your database to a separate machine you'll have to create a domain account and use impersonation in your web.config. Google <identity impersonate="true"> for more info.
If you look in the description of the field it states that running under "Network Services" account is the recommended account to use. Not sure why in Win7 it defaults to the ApplicationPoolIdentity setting.
I have the exact same issue. I'm running Windows 7 RC. When I'm trying to usa a .mdf file (located in App_Data), there is now way to make that thing work. I did try to change the AppPool's identity for LocalSystem, but it simply won't work.
If I use a "standard" database, then it will work if I'm using LocalSystem, but it won't work with the famous 'IIS APPPOOL\DefaultAppPool'.
I find it a bit disturbing not to find any information on that matter, it seems that the 'IIS APPPOOL\DefaultAppPool' user is totally useless if you are using a database of any kind...
I have it running, but I'm also bit frustrated not to understand the security model, as stated by ryexley.
yes, the app pool identity method doesn't work like they say (not in IIS7 anyway) it's supposed to. I think there are hackers at MS who make this security convoluted on purpose so you take the path of least resistance and leave your system less secure (so they can hack into it later). - just kidding, but really, their security model is pure insanity, no straightforward (step by step) instructions anywhere on MSDN - nada, zip!
I faced same problem between (SQL2008 that is installed on standalone Win-server2003 server) and (IIS6 with ASP.NET3.5 that are installed on standalone Win-server2003 server).
Where, IIS tries to access SQL2008 using some user in the domain "domain\username".
I removed following option out of connectionstring, and every thing works fine now.
Integrated Security=True;
Open SQL Management Studio, connect to your local machine as an admin.
Expand the Security branch.
Right click on Logins and select New Login
Into the Login Name field, type "IIS APPPOOL\MyApplicationName". Do
NOT click the search button. The user profile dosn't actually exist
on the local machine, it's dynamically created on demand.
Select Database in User Mapping
Select sysadmin in Server Roles

Resources