When configuring the data source in Asp.net, the following error occurs: object reference is not set to the instance of the object.

Open vs2005 or vs2008,
Create a website and copy the acccess database to app_data,
Drag "accessdatasource" to the window,
Configure the data source...
Select Database
Next step
The SQL statement is empty. Click "Query Builder ..."
Pop-up:

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Microsoft Visual Studio
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You have not set the object reference to the instance of the object.
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OK
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If I do not click "query generator...", but write the SQL statement directly, next, complete, drag a gridview to bind the accessdatasource1 above, and it will run normally.

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All the methods have been tried. If not, set all the services of the system to automatic, start the system, run cmd for half a day, and try again. OK, in this case, it seems that I have shut down the system service, and then restored the system to find that there is no dynamic service, it is also normal, I do not know for you, such as the hacker, please advise.

I think it may be the first time that the system runs what services it needs, and then it does not need to be used later, and I blocked the services it was running for the first time, so it was not successful.