ASP.NET Cannot find server or DSN error

[jjob]

I am new to .NET and am following the MS guided tour at

http://www.asp.net/GuidedTour/default.aspx

I've followed the notes, writing code and adding web forms, and got to the form that is displayed by the url below

http://localhost:2353/AUTHORS/DependencyCaching.aspx

which works if I press F5 at the code, and displays a data grid which has two pages, so the page navigation links appear below the grid. When I use these to move between pages, I get the message shown in the title. If I refresh I get my page back. Sometimes the paging works one way, but not back, sometimes back and not forward. I've looked at the HTML source and the form action is a post back to the page displayed. Anyone any idea why this page doesn't 'page' consistently, or where to look to debug?

There is a masterpage menu which also generates this error, but only on this web form. This web form was copied from an earlier one that works fine, and I believe I've edited it as the MS tour says. So it is definitely something to do with this particular web form.

I'm wondering if it is to do with the Dependency caching, but at the moment don't know where to look.

Thanks in anticipation

 

[jjob]

***************** Apologies ****************

I seem to have fixed it now, I'm afraid to say I think it was simply a case of not stopping the web server during edits - being new to .NET I thought the web server could be left running as I do with IIS, but a couple of pages on in the tour it says if you get odd effects with caching, turn the web server off and then on again!