Issue with display error message in bootstrap with class input-group

[parag075]

             <div class="input-group">
                        <label class="sr-only">Email</label>
                        <input type="email" class="form-control" id="pre_reg_email" name="pre_reg_email" placeholder="Email Address" 
                               data-validation="required" data-validation-error-msg="Email is mandatory field." >
                        <span class="input-group-btn">
                            <button type="submit" class="btn btn-success"> Notify Me ! </button>
                        </span>
                    </div>

Issue is when I use such code orientation of button and input text is getting disturb

[victorjonsson]

This markup won't be supported by the plugin out-of-the-box. The suggestion would be to use data-validation-error-msg-container

Here's an example derived from your code:
http://jsbin.com/xedupavuxu/edit?html,output