STRANGE Error messages in System > Log, Please Help

My website is running fine, but since 2 days i am continuously getting error messages in System > Log
I have noticed that these 2 errors come together at the same time:

Error 1:

Log type:      Unknown
Severity:      11
Message:      This is an invalid script resource request.
Exception:      System.Web.HttpException: This is an invalid script resource request. ---> System.Security.Cryptography.CryptographicException: Padding is invalid and cannot be removed. at System.Security.Cryptography.RijndaelManagedTransform.DecryptData(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount, Byte[]& outputBuffer, Int32 outputOffset, PaddingMode paddingMode, Boolean fLast) at System.Security.Cryptography.RijndaelManagedTransform.TransformFinalBlock(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) at System.Security.Cryptography.CryptoStream.FlushFinalBlock() at System.Web.Configuration.MachineKeySection.EncryptOrDecryptData(Boolean fEncrypt, Byte[] buf, Byte[] modifier, Int32 start, Int32 length, IVType ivType, Boolean useValidationSymAlgo) at System.Web.UI.Page.DecryptStringWithIV(String s, IVType ivType) at System.Web.UI.Page.DecryptString(String s) at System.Web.Handlers.ScriptResourceHandler.DecryptParameter(NameValueCollection queryString) --- End of inner exception stack trace --- at System.Web.Handlers.ScriptResourceHandler.DecryptParameter(NameValueCollection queryString) at System.Web.Handlers.ScriptResourceHandler.ProcessRequestInternal(HttpResponse response, NameValueCollection queryString, VirtualFileReader fileReader) at System.Web.Handlers.ScriptResourceHandler.ProcessRequest(HttpContext context) at System.Web.Handlers.ScriptResourceHandler.System.Web.IHttpHandler.ProcessRequest(HttpContext context) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
IP address:      00.00.00 (Some IP address)
Created on:      5/8/2010 7:09:36 AM





Error 2:

Log type:      Unknown
Severity:      11
Message:      Padding is invalid and cannot be removed.
Exception:      System.Security.Cryptography.CryptographicException: Padding is invalid and cannot be removed. at System.Security.Cryptography.RijndaelManagedTransform.DecryptData(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount, Byte[]& outputBuffer, Int32 outputOffset, PaddingMode paddingMode, Boolean fLast) at System.Security.Cryptography.RijndaelManagedTransform.TransformFinalBlock(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) at System.Security.Cryptography.CryptoStream.FlushFinalBlock() at System.Web.Configuration.MachineKeySection.EncryptOrDecryptData(Boolean fEncrypt, Byte[] buf, Byte[] modifier, Int32 start, Int32 length, IVType ivType, Boolean useValidationSymAlgo) at System.Web.UI.Page.DecryptStringWithIV(String s, IVType ivType) at System.Web.Handlers.AssemblyResourceLoader.System.Web.IHttpHandler.ProcessRequest(HttpContext context) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
IP address:      00.00.00 (Some IP address)
Created on:      5/8/2010 7:09:36 AM

Please guide me why i am getting this error and how i can avoid this error,

These errors can cause big problems or not ?

Please take a look at the screenshot of my admin section > system log

http://img442.imageshack.us/img442/7682/errormessageq.jpg

Having the Same problem in my site now as well.

To nopCommerce Team,
                                    Please guide us in a right direction why we are gettings these errors and how to avoid these error messages ?

This is probably a search engine crawler that posts old/expired information.

Can you track down the used IP address to a crawler? (Try to Google it.)

yes it gives an I.P address , i googled it - it's from U.K

Is this error a serious issue ? or i can ignore this ?

(Just for the information : last week i added my website site map in google - so this error might be from google's side ? )

How i can avoid these kind of errors ?

I'm not 100% sure, but I believe that crawlers are without a session. The scripts that are dynamically generated by .NET are -at least for some parts- based on session information. If the session information is missing, The errors as described might appear in your logs.

If you have submitted your site to Google, please use the  functions that Google offers like 'What Google Sees'.
This will give à good image if the errors do serious harm to your SEO.

Could you please explain me how to use "what google sees" i googled but could not find a solution

i just noticed i got 3 new errors and it is giving location of my blog pages

Error 1:

Log type:      Unknown
Severity:      11
Message:      The state information is invalid for this page and might be corrupted.
Exception: System.Web.HttpException: The state information is invalid for this page and might be corrupted. ---> System.Web.UI.ViewStateException: Invalid viewstate. Client IP: 200.111.76.34 Port: 59758 User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ViewState: 3 Referer: http://www.mywebsite.com/Blog/9-myblog.aspx Path: /Blog/9-myblog.aspx ---> System.FormatException: Invalid length for a Base-64 char array. at System.Convert.FromBase64String(String s) at System.Web.UI.ObjectStateFormatter.Deserialize(String inputString) at System.Web.UI.ObjectStateFormatter.System.Web.UI.IStateFormatter.Deserialize(String serializedState) at System.Web.UI.ClientScriptManager.EnsureEventValidationFieldLoaded() --- End of inner exception stack trace --- --- End of inner exception stack trace --- at System.Web.UI.ViewStateException.ThrowError(Exception inner, String persistedState, String errorPageMessage, Boolean macValidationError) at System.Web.UI.ViewStateException.ThrowViewStateError(Exception inner, String persistedState) at System.Web.UI.ClientScriptManager.EnsureEventValidationFieldLoaded() at System.Web.UI.ClientScriptManager.ValidateEvent(String uniqueId, String argument) at System.Web.UI.Control.ValidateEvent(String uniqueID, String eventArgument) at System.Web.UI.WebControls.TextBox.LoadPostData(String postDataKey, NameValueCollection postCollection) at System.Web.UI.WebControls.TextBox.System.Web.UI.IPostBackDataHandler.LoadPostData(String postDataKey, NameValueCollection postCollection) at System.Web.UI.Page.ProcessPostData(NameValueCollection postData, Boolean fBeforeLoad) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) at System.Web.UI.Page.ProcessRequest() at System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) at System.Web.UI.Page.ProcessRequest(HttpContext context) at ASP.blogpost_aspx.ProcessRequest(HttpContext context) in c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\49f8cc15\b725da54\App_Web_mar2jrjt.13.cs:line 0 at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

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Error 2:

Same error as above but for different blog entry page

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Error 3:

Same error as above but for different blog entry page

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