Asp.net Validation of viewstate MAC failed

Question

I am receiving the following error at certain times on asp.net website.

 Sys.WebForms.PageRequestManagerServerErrorException: 
 Validation of viewstate MAC f         


        

Answer 1

I am not sure how this happened but I started to get this error in my internal submit form pages. So when ever I submit something I'm getting this error. But the problem is this website is almost working 5-6 years. I don't remember I made an important change.

None of the solutions worked for me.

I have setup a machine key with the Microsoft script and copied into my web.config

I have executed asp.net regiis script.

aspnet_regiis -ga "IIS APPPOOL\My App Pool"

Also tried to add this code into the page:

enableViewStateMac="false"

still no luck.

Any other idea to solve this issue?

UPDATE:

Finally I solved the issue. I had integrated my angular 4 component into my asp.net website. So I had added base href into my master page. So I removed that code and it is working fine now.