clone and unzip file in windows
AspDotNetWrapper.exe --keypath MachineKeys.txt --encrypteddata <viewstate> --decrypt --purpose=viewstate --modifier=<__VIEWSTATEGENERATOR> --macdecode
replace the <viewstate>
to viewstate=
parameter value in the source
replace the <__VIEWSTATEGENERATOR>
to __VIEWSTATEGENERATOR=
parameter value in the source