asp.net - Federated Authentication and "Error occurred during a cryptographic operation" -

i got exception when try home page on asp.net mvc application.

[cryptographicexception: error occurred during cryptographic operation.]
system.web.security.cryptography.homogenizingcryptoservicewrapper.homogenizeerrors(func`2 func, byte[] input) +246
system.identitymodel.services.machinekeytransform.decode(byte[] encoded) +191
system.identitymodel.tokens.sessionsecuritytokenhandler.applytransforms(byte[] cookie, boolean outbound) +173
system.identitymodel.tokens.sessionsecuritytokenhandler.readtoken(xmlreader reader, securitytokenresolver tokenresolver) +756
system.identitymodel.tokens.sessionsecuritytokenhandler.readtoken(byte[] token, securitytokenresolver tokenresolver) +100
system.identitymodel.services.sessionauthenticationmodule.readsessiontokenfromcookie(byte[] sessioncookie) +1164
system.identitymodel.services.sessionauthenticationmodule.tryreadsessiontokenfromcookie(sessionsecuritytoken& sessiontoken) +287
system.identitymodel.services.sessionauthenticationmodule.onauthenticaterequest(object sender, eventargs eventargs) +231
system.web.synceventexecutionstep.system.web.httpapplication.iexecutionstep.execute() +80 system.web.httpapplication.executestep(iexecutionstep step, boolean& completedsynchronously) +165

from understand wrong in cookie sessionauthenticationmodule. if clear cookies (as stated here federated authentication on azure) works. understand going on, how catche exceptions , fix issue.

the cookie, when issued, contains security token encrypted using current machinekey. when cookie previous build sent server, sam (more precisely token handler) tries decrypt using new value of machinekey causes error. check answer in related post (federated authentication on azure) mitigate error. hth