http://docs.nopcommerce.com/display/en/FAQ
Q: Error Message: "We're sorry, an internal error occurred. Our supporting staff has been notified of this error and will address the issue shortly..."
A: For version 4.00 and above to find out what went wrong you need to turn off the custom errors mode:
For versions before 4.00 to find out what went wrong you need to turn off the custom errors mode.
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