Can't connect to a SQL server remotely - sql

i'm a new to stackoverflow but maybe i may also ask a question. I also hope i can help others to find solutions regarding their issues.
So, here we go. I moved a database from an old SQL server to a new one. While trying to configure the application to use the new location of that database shows up an error message like this:
Cannot connect to \MSSQLSERVER.
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 25 - Connection string is not valid) (Microsoft SQL Server, Error: 87)
The parameter is incorrect
So i started an analysis to solve this issue. And i checked those things:
DNS resolution -> check
ping to the new SQL Server -> check
Firewall disabled -> check
Remote connections on SQL Server enabled -> check
Still receiving this error message. I configured the SSMS on the application server and ran that as SQL server service user without any success.
SQL Server browser is running
TCP/IP is enabled using the default port 1433
I am not sure regarding the SQL server instance name. IMHO it is shown in the service name and the default instance name is MSSQLSERVER. The error message mentions that the connection string is not valid.
So, at this point i don't have any further ideas.
Greetings,
Chris
[EDIT] I don't use any specific connection string because i connect using SSMS.
enter image description here
[EDIT2]
I was able to connect locally using the hostname (not localhost).
All tests below do not use an instance name
Test Result
-----------------------------------------------------
Locally, hostname, AD Auth Success
Remote, hostname, AD Auth The target principal name is incorrect. Cannot generate SSPI context
Remote, FQDN, SQL Auth Connection string is not valid

Step 1: Login Authentication Windows or SQL Server
Check your login Authentication whether its Windows or SQL Server.
Step 2: Use (.) (dot) instead of complete server name
If you are using local MS sql database then you can use (.) (dot) instead of complete server name.
Step 3: Enter Correct Host Name
Enter your correct host name: (hostname\SQLEXPRESS) my_hostname\SQLEXPRESS (in case of SQL Server Express) or (my_hostname\mssqlserver).
Step 4: Try localhost slash () then host name
You can also try localhost slash () then host name, here is sample as (localhost\SQLEXPRESS) or (localhost\mssqlserver).

Related

I can't open SQL Server 2014 "Cannot connect to server"

After setup I can't open my SQL Server Management Studio:
TITLE: Connect to Server
Cannot connect to 0.
ADDITIONAL INFORMATION:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 53)
The network path was not found
In my case what it worked for me was the Hosts file in the folder C:\Windows\System32\drivers\etc
I was trying to connect into a SQL server with a name that has an entry in the HOSTS file; however, the IP in the HOSTS file was unreachable - Nonexisting -
First, I connected using my SQL client using the IP address and it was no problem.
Next, I delete the entry for the SQL server name in the HOST file in the folder C:\Windows\System32\drivers\etc, saved it and again tried to connect into that SQL server using the name that I just deleted from the host file and it went thru without issues.
I hope it helps someone along the way
It happened for me, but it is nor serious problem. If database is in your local, may be u must boot IIS or SQLEXPRESS manually in Services of Windows.
And may be, you are writing incorrect name.
You can try the following:
In Windows, go to Services >> SQL Server related to your instance >> Right Click >> Start
Again in Services >> SQL Server AGENT related to your instance >> Right Click >> Start
Try connecting the instance again using SSMS.
Regards,
Pratik
The error message is saying Cannot connect to 0. That 0 is where it would normally give the name of the instance it was trying to connect to. Which implies that you gave it 0 as the name of the SQL instance to connect to, which is never going to work.
You need to give it the name of the machine where the SQL server service has been installed (or use shortcuts like . or localhost to represent the current machine) and if the instance name was not the default instance name, you need to follow the machine name with backslash and the instance name.
If you want to connect to the local instance via SQL Server Management. You can expand the server name box and click the . Then you can browse the local servers via expand the "Database Engine". Please click the instance name which you want to connect so that you can avoid fat figures.
Browse for Servers
Besides, if you want to connect to the default instance on the local computer, please specify the server name as "localhost" or " . ". For detailed information, please refer to the document.
https://learn.microsoft.com/en-us/sql/database-engine/configure-windows/logging-in-to-sql-server?view=sql-server-2017

Named pipes provider could not open connection to SQL Server 1231

I am trying to set up a linked server and running into an issue.
On the target server I have configured a user, let's say Q. I have set the source server to connect with Q's login credentials no matter what user is logged in at Source Server.
However when I try to connect, I get the error
"Named pipes provider : could not open a connection to SQL Server
[1231]."
I have tried enabling and disabling named pipes in the server configuration manager, to no avail.
Also I have seen some things saying it is a security problem. The thing is, I am able to connect from Target to Source using Q's credentials in SQL management studio just fine.
Is there something stupid I'm missing here?
is the firewall at the linked server on?
check if the firewall is blocking the named pipes port, which usually is 445
try telnet to the linked server via port 445
Open Server Objects\Linked Servers, then Properties on your linked server. What did you enter here - maybe you are mapping some existing credentials to target credentials?
You should only check the option "Be made using this security context" and then enter Q and it's login. Also, check the "Server Type" to match the destination (Sql server)
On a side note, if the error were due to not supporting of named pipes, I thing you would get a different error, like "error 28 Server doesn't support requested protocol"..

Connect ot SQL Server Express 2012 over the internet

I've been trying to configure my sql server express 2012 to recieve connections over the internet without any luck for hours (I'm using Team Foundation Service for nightly builds but it fails when it tries to run unit tests that interact with the sql server).
All I keep getting is this message :
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
I have tried the following in order to solve this:
Install and run SQL Server Browser
Enable TCP/IP for the sql server instance (using the default SQLEXPRESS)
Enable Port forwarding in my router
Added SQL Server and SQL Server browser apps to the firewall allowed apps list.
Banged my head against the wall.
My sql server is mixed mode, and the username and password are correct (it works when using the local ip address)
I've read every post here regarding this problem but nothing so far..
I'm pretty desperate so any advice will be greatly appreciated!
thanks
Solved it.
Only had to enter my public IP adress without the isntance name.
For example xxx.xxx.xxx.xxx instead of xxx.xxx.xxx.xxx\SQLEXPRESS
I can't believe it's such a stupid mistake ...

Cannot connect to sqlexpress

I just installed of SQL Server Management Studio Express 2012, and then I try to connect database engine with servername : ./sqlexpress, but it failed.
Its raised message like below :
TITLE: Connect to Database Engine
Cannot connect to ./sqlexpress.
ADDITIONAL INFORMATION:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 3)
For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&EvtSrc=MSSQLServer&EvtID=3&LinkId=20476
The system cannot find the path specified.
Whats going wrong?
I've seen this in the past, most likely the wrong instance name or address. Since it is a local DB instance on your machine you will want to try connecting to (local)\SQLEXPRESS [This is the default SQL Express Instance]
If you are running a local instance of SQL Server you can just use localhost as the server name. Also you can try to remove the ./ before the server name.
If anyone else gets a failed to connect to server instance while trying to connect to a DB in C#, make sure you add localhost to the front of your database server address if you're on the same machine.
ie: myDatabase2012
should be put in as localhost\\myDatabase2012 (the second \ is needed to escape the first)

SQL Azure Database Named Pipes Error

Up until last night, my site (hosted by DiscountASP.net) and the SQL Azure database that it connects to were running normally.
For some reason, during the night, the site went down with a named pipe error. Error 40.
Having prefixed the server name with "tcp:" in the connection string, the error is now:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.)
So, just to be clear, the web.config file did not change at all between the time the website last worked and the item the named pipe error came up.
Now, the username, password and instance name are all correct since the site runs locally against the remote SQl Azure server perfectly.
I've checked the instance name and the SQl Azure access rules, ensuring that the web server's IP address is whitelisted.
Any ideas on whats wrong?
If I understand this right, your local website (on-premise) can connect to SQL Azure, but your website deployed in Azure can't?
Make sure your firewall rules has the "allow other windows azure services to access this server". Checking this option off basically prevents any azure-hosted application/service from connecting to your database.