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Log Name: Application
Source: ASP.NET 4.0.30319.0
Date: 06/09/2020 16:09:19
Event ID: 1309
Task Category: Web Event
Level: Warning
Keywords: Classic
User: N/A
Computer: Satie.domain.local
Description:
Event code: 3003
Event message: A validation error has occurred.
Event time: 06/09/2020 16:09:19
Event time (UTC): 06/09/2020 15:09:19
Event ID: d7075c5848ca466f9bae3d9d614c8a0a
Event sequence: 7
Event occurrence: 1
Event detail code: 0

Application information:
Application domain: /LM/W3SVC/33/ROOT-1-132438775749167667
Trust level: Full
Application Virtual Path: /
Application Path: E:\Websites\www\website\
Machine name: SATIE

Process information:
Process ID: 17000
Process name: w3wp.exe
Account name: IIS APPPOOL\website

Exception information:
Exception type: HttpRequestValidationException
Exception message: A potentially dangerous Request.Form value was detected from the client (messagetext="
at System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection)
at System.Web.HttpValueCollection.EnsureKeyValidated(String key)
at System.Web.HttpValueCollection.Get(String name)
at System.Web.UI.WebControls.TextBox.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.ProcessRequest(HttpContext context)
at ASP.contact_aspx.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)



Request information:
https://www.domain.local:443/contact.aspx 
Request path: /contact.aspx
User host address: 134.249.124.67
User:
Is authenticated: False
Authentication Type:
Thread account name: IIS APPPOOL\website

Thread information:
Thread ID: 63
Thread account name: IIS APPPOOL\website
Is impersonating: False
Stack trace: at System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection)
at System.Web.HttpValueCollection.EnsureKeyValidated(String key)
at System.Web.HttpValueCollection.Get(String name)
at System.Web.UI.WebControls.TextBox.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.ProcessRequest(HttpContext context)
at ASP.contact_aspx.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)


Custom event details:

Event Xml:



1309
3
3
0x80000000000000

2335067
Application
Satie.domain.local



3003
A validation error has occurred.
06/09/2020 16:09:19
06/09/2020 15:09:19
d7075c5848ca466f9bae3d9d614c8a0a
7
1
0
/LM/W3SVC/33/ROOT-1-132438775749167667
Full
/
E:\Websites\www\website\
SATIE


17000
w3wp.exe
IIS APPPOOL\website
HttpRequestValidationException
A potentially dangerous Request.Form value was detected from the client (messagetext="
<a href=https://anti...").
at System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection)
at System.Web.HttpValueCollection.EnsureKeyValidated(String key)
at System.Web.HttpValueCollection.Get(String name)
at System.Web.UI.WebControls.TextBox.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.ProcessRequest(HttpContext context)
at ASP.contact_aspx.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)


https://www.domain.local:443/contact.aspx
/contact.aspx
134.249.124.67


False


IIS APPPOOL\website
63
IIS APPPOOL\website
False
at System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection)
at System.Web.HttpValueCollection.EnsureKeyValidated(String key)
at System.Web.HttpValueCollection.Get(String name)
at System.Web.UI.WebControls.TextBox.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.ProcessRequest(HttpContext context)
at ASP.contact_aspx.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

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This is an error with the website you are browsing failing to send an email from the contacts page.

Send the error to the website administrator.