Adding machineKey to machine.config
Just place it under <system.web>
If you need a key generated, use the process as shown in this SO post
Inside <system.web>:
<system.web> <machineKey validationKey="....." decryptionKey="....." />which is at the bottom of the file in mine at least. I don't think the order of elements in system.web matters, as long as it's the top level directly beneath the system.web element.
Get keys from sites can be a risk of security.
there's a simple way to do it, just use your IIS console
The IIS Console open.Click in Computer Keys
The next step is set your keys. Select the appropriate, unflag the boxes to generate manually your keys, and finally click Generate Keys.
Finally, go in your Web.Config and above the set the tags.
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