It takes me a really really really long time to log into xbox.com and any other websites that use my hotmail address. I sometimes get this error:Server Error in '/' Application.
Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.
What does this mean? How can I sort the problem?