Getting "SQL Server does not exist or access denied" error messages

For some reason, this week we started to get "SQL Server does not exist or
access denied" error messages when attempting to connect to our SQL Server
databases. This only affects people who dial into our network. But this
seems to be a rather complicated situation, so let me explain.
We have a couple of VB6 applications we've written. People log into our
network and get authenticated on our network (username, password and domain
must be specified). We have a test server with SQL Server 2000 installed.
The test server is a Windows 2000 Server. The production server has SQL
Server 2000 installed also, but it is a Windows 2003 Server. I have found,
for example, that I can define an ODBC DSN to the test database and retrieve
data just fine, but I can NOT do the same thing to the production database
on the production server. However, our users were able to do so up until
Tuesday of this week. The only thing I can think of which has changed is I
applied the 5 critical updates that Microsoft related Tuesday/Wednesday on
the DHCP server. But the DHCP server is not either the production or test
database servers, so I have no idea why that should make any difference at
all.
Does anyone have any idea why this problem is now showing up?
RodHi Rod,
None of the recent updates would impact SQL or client connectivity
(MDAC).
What is the OS error when the ODBC DSN fails?
Is this only happening over a VPN or can you repro this locally as well?
Thanks,
Kevin McDonnell
Microsoft Corporation
This posting is provided AS IS with no warranties, and confers no rights.|||Hi Rod,
If this is was fine before, then I would suspect that it is an issue related
to the security. Usually this error happens when client does not have
permissions to connect to the SQL Server. Could be that last changes in a
fixes were related to the security issues. Do you know which patches were
installed exactly. If yes, then you could check KB articles for them to see
if installation of them does not change any security settings.
Val Mazur
Microsoft MVP
"Rod" <Rod@.NO.SPAM> wrote in message
news:u05d8jpaEHA.4092@.TK2MSFTNGP11.phx.gbl...
> For some reason, this week we started to get "SQL Server does not exist or
> access denied" error messages when attempting to connect to our SQL Server
> databases. This only affects people who dial into our network. But this
> seems to be a rather complicated situation, so let me explain.
> We have a couple of VB6 applications we've written. People log into our
> network and get authenticated on our network (username, password and
> domain
> must be specified). We have a test server with SQL Server 2000 installed.
> The test server is a Windows 2000 Server. The production server has SQL
> Server 2000 installed also, but it is a Windows 2003 Server. I have found,
> for example, that I can define an ODBC DSN to the test database and
> retrieve
> data just fine, but I can NOT do the same thing to the production database
> on the production server. However, our users were able to do so up until
> Tuesday of this week. The only thing I can think of which has changed is I
> applied the 5 critical updates that Microsoft related Tuesday/Wednesday on
> the DHCP server. But the DHCP server is not either the production or test
> database servers, so I have no idea why that should make any difference at
> all.
> Does anyone have any idea why this problem is now showing up?
> Rod
>
>|||I am having a similar problem. i am not very experienced programmer and
wrote a program in vb.net which connected fine to my local copy of sql.
the db admin set up ODBC's for the remote servers and i got the same
error. i tried using odbc's on my local machine and fixing the
problem, but i can't for the life of me figure it out. When i test the
connection in the odbc setup,it connects great. i just cannot do it
via the program. I used the odbc connection string and put the
passwords and id in the string code before i try to open the
connection. very confused. any help would be greatly appreciated.
thanks
Chris
Val Mazur wrote:[vbcol=seagreen]
> *Hi Rod,
> If this is was fine before, then I would suspect that it is an issue
> related
> to the security. Usually this error happens when client does not
> have
> permissions to connect to the SQL Server. Could be that last changes
> in a
> fixes were related to the security issues. Do you know which patches
> were
> installed exactly. If yes, then you could check KB articles for them
> to see
> if installation of them does not change any security settings.
> --
> Val Mazur
> Microsoft MVP
>
> "Rod" <Rod@.NO.SPAM> wrote in message
> news:u05d8jpaEHA.4092@.TK2MSFTNGP11.phx.gbl...
> exist or
> Server
> this
> our
> and
> installed.
> SQL
> found,
> and
> database
> until
> changed is I
> Tuesday/Wednesday on
> or test
> difference at
ringo
---
Posted via http://www.mcse.ms
---
View this thread: http://www.mcse.ms/message862704.html|||So, if local connections work, but remote connections fail. I would
suggest making some network traces to verify that we're using the right
protocols and able to resolve the machine name.
run the following commands from a DOS prompt:
ipconfig /flushdns
ipconfig /registerdns
Then.
start Microsoft Network Monitor
Attempt a connection using your program.
stop Microsoft Network Monitor.
Review the trace.
Thanks,
Kevin McDonnell
Microsoft Corporation
This posting is provided AS IS with no warranties, and confers no rights.|||I believe I have found the problem. The user has Norton Internet Security
2003 (or 2004, I am not sure which) installed. Once I disabled that, I was
able to reach the server.
Rod
"Kevin McDonnell [MSFT]" <kevmc@.online.microsoft.com> wrote in message
news:AjXJoyAdEHA.3808@.cpmsftngxa10.phx.gbl...
> So, if local connections work, but remote connections fail. I would
> suggest making some network traces to verify that we're using the right
> protocols and able to resolve the machine name.
> run the following commands from a DOS prompt:
> ipconfig /flushdns
> ipconfig /registerdns
> Then.
> start Microsoft Network Monitor
> Attempt a connection using your program.
> stop Microsoft Network Monitor.
> Review the trace.
> Thanks,
> Kevin McDonnell
> Microsoft Corporation
> This posting is provided AS IS with no warranties, and confers no rights.
>
>|||Kevin , thanks for your response.
I may not have been as clear as i should have been. After the initial
failed attempt of putting the program onto a local computer with the DB
on a separate server, i tried to re-create the problem on my own
laptop. I have made an ODBC which calls the sql on my machine. My
theory is that this would recreate the same process as if it were on a
centralized server. I still get the SQL SERVER DOES NOT EXIST OR
ACCESS NOT DENIED. I don't get it tho. when i create the ODBC, it
tests successfully. Also, when i create a new connection string, and
choose ODBC driver and the correct odbc name (which appears, so it sees
the odbc list) IT also tests successfully. However, when i try to run
the program just opening the conn, it gives the error. I thought i had
fixed it becuase one odbc name i created happened to be the same name
as my local server, so it didnt' give the error, but im thinking it
didn't use the odbc, it just called the local server.
I did the ipconfig/ things you suggested. I am not familiar wiht
Microsoft Network Monitor. Should i continue with this possible
resolution?
thanks so much,
Chris
Kevin McDonnell [MSFT] wrote:
> *So, if local connections work, but remote connections fail. I
> would
> suggest making some network traces to verify that we're using the
> right
> protocols and able to resolve the machine name.
> run the following commands from a DOS prompt:
> ipconfig /flushdns
> ipconfig /registerdns
> Then.
> start Microsoft Network Monitor
> Attempt a connection using your program.
> stop Microsoft Network Monitor.
> Review the trace.
> Thanks,
> Kevin McDonnell
> Microsoft Corporation
> This posting is provided AS IS with no warranties, and confers no
> rights. *
ringo
---
Posted via http://www.mcse.ms
---
View this thread: http://www.mcse.ms/message862704.html|||Hi Ringo,
Unfortunately, you can't make network traces of local connections. Try
using ISQL.exe locally to see if it will generate the OS error for you.
Also check the HKLM\Software\Microsoft\MSSQLServer\Clie
nt\ConnectTo key:
the only entry should be DSQUERY set to DBNETLIB.
Thanks,
Kevin McDonnell
Microsoft Corporation
This posting is provided AS IS with no warranties, and confers no rights.sql