Loss of ODBC connections 1

[StevenK]

Not so much a query about SQL Server - more so about a problem we are facing on accessing it through ODBC. We have an application developed in Delphi 5 that works against a SQL server 7.0 database on a server from the local client machines. We are using an ODBC connection through which we connect the database component and 1then respective data-aware components. Two machines on our site have been found to lose their ODBC connections that were set up to access the database. We are then unable to re-create the ODBC connection through the ODBC Source Administrator - after indicating the server-name and entering a user-name/password for authentication the machine hangs after clicking the 'Next' button. The only way we have found to re-create this ODBC connection is by a re-install of the operating system. This problem is tempremental in the sense that one day the ODBC source is present and the application can be used and then the next day the ODBC connection is no longer there for use. The two machines in question have Windows '95 and Windows '98 as their operating system - other machines with the same OS do not have this problem.
Does anyone know of any software that would cause the loss of ODBC source connections or can anyone provide us with some pointers ?

Thanks in advance.
Steve

 

[foxdev]

I've never experienced this, and it sounds like you've done a good job trying to isolate the issue. My only WAG suggestions are:

* explicitly install the latest MDAC on the problem machines

* try using a System DSN rather than User DSN (no idea why this would help, but its simple to try)
Robert Bradley

http://www.lowcostprints.com

http://www.foxdev.com

 

[StevenK]

foxdev - Thanks for the suggestions.
We have looked at the machines and determined that the version of MDAC is 2.5 on all of them. Having looked on the web it is indicated to not use version 2.6 if working against SQL server 7.0 due to problems with clusters.
The ODBC connection is set up as a System DSN on all of the machines.
The other thing that we have as part of the configuration of the ODBC connections is that we have used the 'Client Configuration' button and indicated TCP/IP (indicating port 1443) in place of the default 'Named Pipes' as this was the only way in which the individual was able to make a connection to the SQL server database on the server. A colleague has suggested that another piece of software may lock this port (software like the mail-software for instance) and that this may be the cause of the problem.
Does the fact that we are connecting using TCP/IP lead anyone to any more thoughts on this problem ?
Thanks again ..
Steve

 

[foxdev]

Two machines on our site have been found to lose their ODBC connections (...) We are then unable to re-create the ODBC connection through the ODBC Source Administrator - after indicating the server-name and entering a user-name/password for authentication the machine hangs after clicking the 'Next' button.

Does this mail software run on the other machines that are working fine?

I'm down to random ideas at this point. Try using Multiprotocol rather than TCP/IP. Are you using NT security or standard mode? If using NT only, try switching to standard. If Delphi supports it, try using a DSN-less connection (e.g. connection string). Robert Bradley

http://www.lowcostprints.com

http://www.foxdev.com

 

[davidllittle]

Steven, A shot in the dark here ok! I have had similar problems with some machines where I had to update this file - "SQLSRV32.DLL" from a machine that was working. I cant give the technical explanation but can tell you it fixed my problem. The current version # under the odbc driver tab shows the current version your running. Some versions of this driver just dont work?

 

[StevenK]

foxdev - the mail software mentioned (Lotus cc-mail) does run on all the machines. We'll look at compiling a version of the application with a DSN-less connection.
davidlittle - I will look into the issue of the version of 'SQLSRV32.DLL' on the suspect machines and compare them to the versions on the operational workstations.
Thanks for the advice chaps.
Steve

 

[JoT]

I know you started this thread ages ago, but did you ever get to the bottom of it? I ask because I am now experiencing a similar problem: trying to connect to a remote SQL Server db using ODBC - was able to establish a connection once when setting up DSN (using named pipes) but never again!

Thanks.

 

[mothball]

I am having the same problem, immediately after Office SP1 & SP2 and XPSP1 update. Any fixes work