Long Running Operations

The problem:

I have a long-running operation that is supposed to transfer to an error page in case of an error.

This code is perfectly valid. However, the error page (SPUtility.ErrorPage, which is just a synonym for error.aspx) it transfers to is too generic ("An error has occurred on the server") and cannot be customized with a more informative error message.

The solution:

You don't have to call the End() method for the long operation; if the result is erroneous, make a transfer to the error page using SPUtility.TransferToErrorPage, which takes an error message as a parameter. This code does the trick. Note also that it catches ThreadAbortException.