Occurs when a data source is configured under ASP.net: An object reference is not set to an instance of an object. _ Practical Tips

Open vs2005 or VS2008,
Create a new Web site, copy the acccess database to App_Data,
Drag "AccessDataSource" into the window,
Configure Data Source ...
Select Database
Next
The SQL statement is empty, point "Query Builder ..."
Pop:

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Microsoft Visual Studio
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An object reference is not set to an instance of an object.
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Are you sure
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If I don't click "Query Builder ..." instead, write the SQL statement directly, and the next step, complete, drag a GridView to bind the AccessDataSource1 above, and it works.


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All the methods have been tried, no, and then all the services of the system are set to Automatic, then start, cmd Half-day, and then try, OK, so it seems to be the system which service I give off, and then restore the system found no dynamic service, also normal, do not know for you, such as the person who know, please advise.

I felt like it was probably the first time the system was going to run, and then it didn't work out, and I stopped the service from his first run, so he didn't make it.