I have been getting feedback from many Contact Form 7 users everyday. It gives me great pleasure to hear the voices of the users.
Some of what I hear, however, are reports of trouble. These resports are helpful to me in detecting bugs in the plugin, or to give me suggestions for enhancements to the plugin and documentation of it.
However, most of the recent reports of trouble that I have been getting are not with Contact Form 7. I find that most of the problems are caused by other issues, in particular, their invalid HTML structure, or conflicts with JavaScript which is loaded improperly by other plugins or themes.
In such cases, I can do nothing but tell them, “You should check your site and correct errors in it. This issue is actually caused by other plugins or theme you are using, and not a trouble of Contact Form 7” But even when I make that clear to them, some of them keep claiming that there is a bug in Contact Form 7.
So I ask you users, before reporting trouble to me, please check your site on your own first:
Check your site with HTML validators and correct errors. Contact Form 7, as well as many other plugins, uses JavaScript to manipulate DOM objects represented by HTML. So if your HTML structure is not valid, the JavaScript can’t work correctly, of course.
There are many HTML validators, but I always recommend XHTML-CSS Validator as it has a cool appearance and is easy to use.
Even if HTML is okay, JavaScript conflicts between plugins or themes can cause errors. If you use Firefox (I highly recommend Firefox if you develop web sites), you can use the excellent Firebug to check JavaScript errors.
This is the trouble pattern I see these days most often. Some plugins and themes try to load JavaScript files in an improper way. And this results in the loading the same JavaScript files multiple times, and causes conflicts.
Open the HTML source of your problematic page and check it out. Do you find jquery.js in two or more places? If so, contact the developer of the plugin or theme which loaded the JavaScript, and ask him or her to look at this Codex page and fix the issue by using wp_enqueue_script(), instead of loading JavaScript in its own way.
Unfortunately, I don’t have enough time to answer all the reports of trouble or the support requests individually, so I won’t respond to them any more if you have not followed the steps above and checked your own site first.
If you have trouble but you don’t have the skills to check your site, and don’t know how to fix the problem, please submit your issue to the support forum with the URL of the site where the issue exists. Someone will check it the problem for you and help you fix it.