Microsoft has released a Knowledgebase Article which provides details on how to enable a new security feature in Windows Vista SP1 called Structured Exception Handling Overwrite Protection (SEHOP). Microsoft recommends that users enable this feature as it provides additional protection against exploits, however note that there are known issues with Cygwin, Skype and Armadillo-protected applications.
Click here to see how.
Click here to see how.