I've run into a strange problem where data entered into the site (example: changing the name of a web page) often doesn't post immediately after hitting the update link. It used to, just not any more. And the web pages are loading just fine, they just don't show the new data. The problem seems to be when the browser refreshes after a setting is changed but when it goes back to the db for the data it misses it. The really tough part I'm dealing with here is that the results are so spuratic. One time data will post immediately, the next time (doing the exact same thing) it won't, and then maybe the third time it will post a similar change imediately again.

I am running:

• DNN 4.6.0
• Windows server 2000
• MSSQL 2003
• New Dell web server with lots of power and speed

I have tried the following:

• Changing the cache and performance settings under Host > Site settings = no effect
• Changing the cache settings on the server = no effect
• Checked different browsers = happens in both IE and Firefox, maybe a little less in IE but not conclusive
• Changed IE setting to check for new version of page every time = no effect
• Rebooted the web server = no effect
• Removing modules that were installed the week prior to the issue (xmod, venexus search) = no effect
• Currently looking into a child portal site where I have found the following error (would this be relatedto the issue I'm having?):
  • A critical error has occurred.
    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.

Does anyone know of a solution to this problem? 
Thanks in advance
Mike

ok, thanks for your response. Our server manager had set up a "development" DNN site that mirrors the current one. Could this possibly be the culprit? Currently I believe the way its set up is the web server is running the production version of the site and another physical server is running the dev version but they are sharing the same sql server although writing to different databases.
Thanks for helping me narrow my trouble shooting,
Mike

Thanks for all your help. We followed the recommendations above and the site appears to be posting data correctly again. Thanks so much!