How To Solve
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.
I know it's old, but it would have helped me to find a solution to this on GoDaddy's website. Since I figured it out, I wanted to post my solution.
Copy the Powershell Script
Run it on your machine
It will generate a Machine Key for you
Copy the static machine key value from Powershell, add it to your web.config in the <system.web> section, and redeploy your project.
This worked for me and is the supported method found in many forums where your hosting account is managed by GoDaddy.
I added machine key to the Web.config and deployed. However, I keep getting an Internal Error.
I also tried added <pages enableViewStateMac=”False” /> to the web.config file. Temporarily of course, just to stop the annoying error.
Yet it does not solve my problem.
Any help appreciated.
Thanks in advance.
Have you tried? this link - it won't solve the problem, but it may give you more details to the error and help you isolate your issue.
Another option might be to post the error message in the forum. I would normally want to look at the Web.config, but that can contain information you may not want to share, so I would not recommend posting it. Your best option might be to call GoDaddy at this point.
Here's the article:
I have come to the same problem and fixed the same way as Alex K.
So if "Send Errors To Browser" is not working set also this:
Error Pages -> 500 -> Edit Feature Settings -> "Detailed Errors"
Also note that if the content of the error page sent back is quite short and you're using IE, IE will happily ignore the useful content sent back by the server and show you its own generic error page instead. You can turn this off in IE's options, or use a different browser.