BotDetect CAPTCHA ASP.NET FAQ (BotDetect v3.0; deprecated)
This page answers frequently asked questions about various technical aspects of BotDetect ASP.NET Captcha functionality.
- BotDetect integration & deployment FAQ
- BotDetect persistence requirements & options FAQ
- BotDetect Captcha validation & security
CAPTCHA Integration & Deployment FAQ
This page contains answers to frequently asked questions about BotDetect ASP.NET CAPTCHA integration in various kinds of ASP.NET projects and deployment to common server configurations.
- Why does BotDetect Captcha require registering a
HttpHandlerin my ASP.NET projectweb.config? - I am trying to implement BotDetect Captcha and I see the sample page references
BotDetectCaptcha.ashx, but there is no such file in the downloaded zip. Can you help? - I'm trying to add BotDetect Captcha to my ASP.NET form, but the Captcha image is missing. What can I do?
- Is BotDetect ASP.NET Captcha compatible with IIS 7? Everything works on IIS 6.0, but when I deploy my project to IIS 7, the Captcha image is missing.
- I'm trying to add BotDetect Captcha protection to my
Login.aspxpage, presented to the user before he is authenticated. However, the Captcha image fails to display for non-authenticated users. I am using Forms Authentication, so I cannot use your sampleweb.configfile as is. - I'm trying to integrate BotDetect Captcha in my project, but the
HttpHandlerregistration doesn't seem to work with Url Rewriting. Is there a way around this? - Can I change the handler path used for BotDetect Captcha requests?
- Does BotDetect Captcha work with ASP.NET MVC? Can BotDetect Captcha protection be added to Razor Views?
- I'm trying to add BotDetect to my ASP.NET MVC application, but I'm getting
"Could not load file or assembly 'System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference."errors when I try to run it. Your component seems to be referencing an older version of ASP.NET MVC, which is not installed on my system. - Your ASP.NET MVC integration instructions start by adding a
CaptchaCodefield to a Model class, which conflicts with our requirements. Can we add BotDetect Captcha protection to a Controller action without adding any fields to the Model declarations? - How do I use localized Captcha validation error messages from ASP.NET MVC application resources? If I use
[CaptchaValidation("Captcha", "RegistrationCaptcha", Resources.Error.CaptchaMismatch)], I get"An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type"errors. - I've chosen the "Deploy to IIS" option during BotDetect installation, but the samples weren't deployed to IIS. Why?
- Are there any additional steps I need to do when upgrading the component to a newer version? When I update the
BotDetect.dllassembly in my project to the new release, I get a"The located assembly's manifest definition does not match the assembly reference"runtime error. - My host no longer permits Full Trust security levels. Does BotDetect Captcha run in ASP.NET Medium Trust?
CAPTCHA Persistence FAQ
This page contains answers to frequently asked questions about BotDetect ASP.NET CAPTCHA persistence requirements and options.
- Is ASP.NET Session State Required for BotDetect Captcha?
- Why Exactly is ASP.NET Session State Required for BotDetect?
- Why doesn't BotDetect offer a client-side persistence option? After all, other Captcha services don't store everything in the Session, but rather transfer an ID or a hashed token to the client.
- Why does BotDetect require specifying the
<sessionState> sessionIDManagerTypeattribute inweb.config? - Our ASP.NET application already uses a custom
SessionIDManager. Will this cause a clash with the BotDetect customSessionIDManager? - Can I use BotDetect ASP.NET Captcha in a Web Farm / Web Garden?
- How do I enable ASP.NET Session State in SharePoint server? I keep getting
SessionTroubleshooting: SessionHttpModule not runningerrors. - We're trying to use BotDetect Captcha on a form that is
<iframe>-d into another page that's on a different domain. The Captcha works in Firefox, but not in IE (version 6 or 7). Have you seen this problem before? - After adding BotDetect Captcha to my form, I've noticed that the first time I access the page the URL modifies itself by adding a querystring:
AspxAutoDetectCookieSupport=1. This querystring disappears on the next request, but I'm wondering is it possible to hide it completely? - Adding BotDetect to the application broke my ASMX SOAP web service residing in the same project. What can I do?
- We currently use your BotDetect ASP.NET CAPTCHA control and I have a question regarding ASP.NET Cache. I have noticed a number of items being added to our web application cache named
'LBD_CaptchaRequestTracker_...'
Could you tell me why are these cache items created, and what are their timeout parameters?
CAPTCHA Validation & Security FAQ
This page contains answers to frequently asked questions about BotDetect ASP.NET CAPTCHA validation and security.
- Why can't users correct their Captcha code input when they get it wrong? If they make a mistake, it seems they have to type in a whole new code from a new image.
- I have a form protected with BotDetect Captcha that contains several other validated fields. When a user enters the correct Captcha code but server-side validation of another field fails, they are shown another Captcha image with a different code.
Is there a way to show them the same Captcha image and keep the entered code, so they don't have to solve more than one Captcha just because they entered an invalid value for another field? - I want to validate the Captcha on the client side without doing a post back. Do you have any suggestions? Is it possible to retrieve the current Captcha code at
Page_Load, and send it to the client? - Is it possible to validate the user Captcha input in a static context (outside the the ASP.NET Web Form lifecycle)?
- What is the difference between
ValidationOrigin.ServerandValidationOrigin.Client? - I implemented BotDetect Captcha protection, but my form is still getting some suspicious submissions. How can I check that the Captcha validation works?
- Captcha validation seems to work properly, but submitted data is suspicious. Could a bot be bypassing the Captcha?
- Occasionally my web site is seeing an excessive number of Http requests to
BotDetectCaptcha.ashx. The number of requests is more than 100x the count of other path requests for the same period. Do you have any idea what is going on?
Please Note
The information on this page is out of date and applies to a deprecated version of BotDetect™ CAPTCHA (v3.0).
An up-to-date equivalent page for the latest BotDetect Captcha release (v4) is BotDetect v4 Captcha documentation index.
General information about the major improvements in the current BotDetect release can be found at the What's New in BotDetect v4.0 page.
Current BotDetect Versions
-
BotDetect ASP.NET CAPTCHA
2019-07-22v4.4.2 -
BotDetect Java CAPTCHA
2019-07-22v4.0.Beta3.7 -
BotDetect PHP CAPTCHA
2019-07-22v4.2.5
