ASP Net logoff issue

It looks like your issue is related to "Maximum request length exceeded", which can cause unexpected logouts when postback events fire. Here are some possible fixes:

1. Increase `maxRequestLength` in `web.config`

Your postback might be sending a large amount of data (e.g., ViewState, form data). Try increasing the request length in web.config:

This increases the maximum request size to 32 MB.

2. Reduce ViewState Size

Even though you set EnableViewState="true", excessive ViewState can cause large postback sizes. Try disabling ViewState for unnecessary controls:

3. Check IIS Request Filtering

If your application is hosted on IIS, you may need to adjust the maxAllowedContentLength setting:

This increases the allowed request size to 30 MB.

4. Debug Global.asax Events

Since your debugger enters Global.asax, check if Session_End or Application_Error is triggering a logout. You can log session expiration events:

protected void Session_End(object sender, EventArgs e)
{
    // Log session expiration
    System.Diagnostics.Debug.WriteLine("Session expired!");
}

5. Check Authentication Timeout

If your authentication session is expiring too quickly, increase the timeout in web.config:

This sets the session timeout to 60 minutes.

6. Use UpdatePanel Correctly

If you're using an UpdatePanel, ensure that triggers are correctly set:

Try these fixes one by one and see if your issue is resolved. If the logout still happens, check event logs in IIS or Global.asax for unexpected session expirations.

1 Reply

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Deepika Sawant1y ago
It looks like your issue is related to "Maximum request length exceeded", which can cause unexpected logouts when postback events fire. Here are some possible fixes:

1. Increase maxRequestLength in web.config

Your postback might be sending a large amount of data (e.g., ViewState, form data). Try increasing the request length in web.config:
```
  
    
  
```
This increases the maximum request size to 32 MB.

2. Reduce ViewState Size

Even though you set EnableViewState="true", excessive ViewState can cause large postback sizes. Try disabling ViewState for unnecessary controls:
3. Check IIS Request Filtering

If your application is hosted on IIS, you may need to adjust the maxAllowedContentLength setting:
```
  
    
      
        
      
    
  
```
This increases the allowed request size to 30 MB.

4. Debug Global.asax Events

Since your debugger enters Global.asax, check if Session_End or Application_Error is triggering a logout. You can log session expiration events:
```
protected void Session_End(object sender, EventArgs e)
{
    // Log session expiration
    System.Diagnostics.Debug.WriteLine("Session expired!");
}
```
5. Check Authentication Timeout

If your authentication session is expiring too quickly, increase the timeout in web.config:
```
  
    
      
    
  
```
This sets the session timeout to 60 minutes.

6. Use UpdatePanel Correctly

If you're using an UpdatePanel, ensure that triggers are correctly set:
```
    
        
    
    
        
    
```
Try these fixes one by one and see if your issue is resolved. If the logout still happens, check event logs in IIS or Global.asax for unexpected session expirations.