If you are getting hammered by spam registration here is a quick fix that doesn't require any coding or application upgrades or special recaptcha.

 

1. Create a custom profile field.
2. Assign a value for the "Validation Expression" attribute of the profile field. (You get to set your own value like "1234", or "DNN Rocks"
3. Set the field to required
4. Change the property name to indicate the value the user is supposed to enter. (This will be the label like "Enter 1234" make sure the property name tells users what they need to enter.
5.  Save the changes
6. In Registration Settings check the "Require a valid Profile for Registration"  

This completely stopped spam registrations for my clients. Basically what you have done is create a custom non standard captcha field that spammers code can't find. In general spammers create code for use on as many sites as possible. Since each DNN site will have a different value for the custom field, the spammer's crawler won't know where to enter the custom validation text, or if the text even exists.

 

Since the field is required for registration no user profile will be created and your hosting provider won't shut you down for having too big a database from spammer registrations.

    We also use a similar method to stop spammers. Check http://dnnmodule.com and try click the "Register" button, you will see it ask you input a specific word (currently "dnn") to register, it works prefect. However, we do this by modify DesktopModules\Admin\Security\Register.ascx (and Register.ascx.cs). 

     I like to share our modification. If anyone needs our modified files, just contact me at xiaoqi98@msn.com.

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