VS2010 will not automatically eliminate the errors. But it offer several new featuers for better debugging and troubleshooting.
You can take a look at the 'Saving test logs' feature mentioned above, with it, you can find what the failed web test did during load test running to figure out whether there are some parameter lost, etc.
In addition, if you manually access the requests in web test during load test running, are there any errors?
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