Thread: ML 8 - Unable to validate data

I moved two ASPDOTNET Storefronts to a new server:
Windows Server 2008 R2 Standard
IIS 7.5

I find some error messages in the application log and had a couple of customers calling to let me know that they can't access the site.

I invalidated the login cookies.

I personally don't have this problem and tested with IE 8, IE 9, Chrome, Firefox 10, Firefox 6 (was a problem).

Has anybody had the same problem?
Does anybody know the solution to fix this issue?

I'll copy the error message below.

Any help is very much appreciated.

Karl

ERROR MESSAGE:
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 05/03/2012 11:27:32
Event time (UTC): 05/03/2012 11:27:32
Event ID: dd50dcc8d49143cc96eca5a2023827b0
Event sequence: 636
Event occurrence: 57
Event detail code: 0

Application information:
Application domain: /LM/W3SVC/12/ROOT-3-129753894176026369
Trust level: Full
Application Virtual Path: /
Application Path: "I removed the path"
Machine name: NS1

Process information:
Process ID: 2784
Process name: w3wp.exe
Account name: IIS APPPOOL\"The application pool IIS created for the site"

Exception information:
Exception type: HttpException
Exception message: Unable to validate data.

Request information:
Request URL: https://www.v4vitamins.co.uk:443/sho...-mineral-drops
Request path: /showproduct.aspx
User host address: "Removed the host address"
User:
Is authenticated: False
Authentication Type:
Thread account name: IIS APPPOOL\"as above"
Thread information:
Thread ID: 7
Thread account name: IIS APPPOOL\"as above"
Is impersonating: False
Stack trace: at System.Web.Configuration.MachineKeySection.Encrypt OrDecryptData(Boolean fEncrypt, Byte[] buf, Byte[] modifier, Int32 start, Int32 length, IVType ivType, Boolean useValidationSymAlgo, Boolean signData)
at System.Web.Configuration.MachineKeySection.Encrypt OrDecryptData(Boolean fEncrypt, Byte[] buf, Byte[] modifier, Int32 start, Int32 length, IVType ivType, Boolean useValidationSymAlgo)
at System.Web.Security.FormsAuthentication.Decrypt(St ring encryptedTicket)
at AspDotNetStorefront.Global.Hs8ObwsQk(Object , EventArgs )
at AspDotNetStorefront.Global.Application_Authenticat eRequest(Object sender, EventArgs e)
at System.Web.HttpApplication.SyncEventExecutionStep. System.Web.HttpApplication.IExecutionStep.Execute( )
at System.Web.HttpApplication.ExecuteStep(IExecutionS tep step, Boolean& completedSynchronously)

I've got this reply from support:

"I believe what you would have had to do is set a static machine key in the web.config :

http://manual.aspdotnetstorefront.co...on-wizard.aspx (Set Static Machine Key)

Since you probably have not done this, the new server has generated a different machine key than you had previously, invalidating the cookies."

Does anyone know if setting the machine key will solve the problem or make it worse as the visitors who don't have a problem will get one?

I am really deperate for a solution as it effects most likely existing customers.

Thanks, Karl