Validation of viewstate MAC failed.

[Chris]

I am getting an intermittant 'Validation of viewstate MAC failed' when
people go to a particular page. I have tried setting:

enableEventValidation="false"
viewStateEncryptionMode ="Never"

in the page directive which seems to be the general fix. I am using a link
button to navigate to the page and I can't remember why did this but I
changed the postback URL to the page throwing up the error rather than just
using a link. Would posting to the page rather than a link cause my page to
see this as some kind of spoofing? As I have tried a variety of things I
would like to know which one is solving the problem.

 

[Guest]

I am getting an intermittant 'Validation of viewstate MAC failed' when
people go to a particular page. I have tried setting:

enableEventValidation="false"
viewStateEncryptionMode ="Never"

in the page directive which seems to be the general fix. I am using a link
button to navigate to the page and I can't remember why did this but I
changed the postback URL to the page throwing up the error rather than just
using a link. Would posting to the page rather than a link cause my page to
see this as some kind of spoofing? As I have tried a variety of things I
would like to know which one is solving the problem.

Maybe you can try this to see if it helps
http://www.andreas-kraus.net/blog/validation-of-viewstate-mac-failed/

 

[Chris]

Thanks but I've tried that as well. Could setting the postbackURL to the
newpage rather than linking it cause the problem. Ideally I want to know
exactly what and why the problem occurs rather than try a variety of things
and it just go away. Regards, Chris.