It's hard to say with certainty, but I do have a guess. :)
First, understand that there are certain "providers" installed on the computer along with the operating system. OLEDB happens to be one of them.
In order to use a certain provider, you may need to install it. You mentioned that this is a classic asp site you are working on, which probably simplifies things a bit because you would only need to install the provider on the web server.
There is a way you can tell which providers are installed on a computer. Right click the desktop, click New, Click Text Document. Change the extension to UDL, and then double click on this file. You should see a window called "Data Link Properties". Click on the "Provider" tab.
At this point, you will see a list of providers that are installed on the computer. I guarantee you will see "Microsoft OLEDB Provider for SQL Server" because you said this one works. I suspect you will NOT see "SQL Server Native Client 10.0" (when you do this on the web server).
To install the provider, go to:
There are a lot of things to download on this page. If your server has a 64 bit operating system, then you will want this one: 1033\x64\sqlncli.msi
If the server has a 32 bit operating system, get this one:
Once you install the provider on the web server, you should be able to use it in your connection string.
Microsoft SQL Server MVP
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