SeanSF

Robbie, the sleep/standby mode issue in Vista, for me at least, was due to the driver used by my Intel NIC on my Dell Dimension 9200. Peruse the threads of this posting and find the link sander0501 posts to get a app from Intel that will update the features and capabilities of that NIC. This should resolve your issue, if your conditions are like mine. Either way, look into the driver for your NIC just in case. If, when you come out of standby, your computer is 'unauthenticated' but your can get it to re-authenticate by diabling and enabling your NIC, then the variable in this issue is likley your NIC/NIC driver.