Troubleshooting CryptographicException in ASP.NET application

I want the following error to be solved. The website is NOT no a web farm. --------------------------------------------------------- Computer : 2COLT863 Log : Application Source : ASP.NET 2.0.50727.0 Level : Warning Category : Web Event Id : 1309 Time : 3/8/2007 3:40:49 PM User : Event code: 3005 Event message: An unhandled exception has occurred. Event time: 3/8/2007 3:40:49 PM Event time (UTC): 3/8/2007 2:40:49 PM Event ID: 2f7d9705815b40a69994c2aff470940d Event sequence: 25014 Event occurrence: 16 Event detail code: 0 Application information: Application domain: /LM/W3SVC/657964845/Root-1-128177858291298750 Trust level: Full Application Virtual Path: / Application Path: D:SitesDolcevitaNET2www Machine name: 2COLT863 Process information: Process ID: 1972 Process name: [login to view URL] Account name: NT AUTHORITYNETWORK SERVICE Exception information: Exception type: CryptographicException Exception message: Padding is invalid and cannot be removed. Request information: Request URL: [login to view URL];t=632606889930000000 Request path: /[login to view URL] User host address: [login to view URL] User: Is au thenticated: False Authentication Type: Thread account name: NT AUTHORITYNETWORK SERVICE Thread information: Thread ID: 1 Thread account name: NT AUTHORITYNETWORK SERVICE Is impersonating: False Stack trace: at [login to view URL](Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount, Byte[]& outputBuffer, Int32 outputOffset, PaddingMode paddingMode, Boolean fLast) at [login to view URL](Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) at [login to view URL]() at [login to view URL](Boolean fEncrypt, Byte[] buf, Byte[] modifier, Int32 start, Int32 length, Boolean useValidationSymAlgo) at [login to view URL](String s) at [login to view URL](HttpContext context) at [login to view URL]() at [login to view URL](IExecutionStep step, Boolean& completedSynchronously) Custom event details: