If you have an online form and you've been receiving 'blank' or 'spam' enquiries through this form, most likely because there is no “validation” on the form. This means that someone can simply hit submit, without filling out anything in the form. The majority of these “blank” enquiries are not users submitting. Rather it is an automated program visiting your site to catalogue content (some of these programs are malicious, and are “scanning” your site for vulnerabilities). 

If you are receiving enquiries filled with random text, again this is an automated program submitting your form with useless information, to see what content is on the next page. This could also be an attempt to see if this form can be compromised. Poor “validation” can lead to more spam being allowed through. 

We highly recommend installing a “humanity” check (also known as a “CAPTCHA”). A humanity check is usually a graphic containing a series of words or letters, see sample below. These letters / words need to be entered before a form can be submitted. As these words and letters are often jumbled and distorted, automatic spam 'robots' cannot lodge these forms (i.e. it requires a human to decipher the text, and then enter it).