If you are using Javascript / Ajax to submit the form, make sure you set the Headers accordingly. Setting wrong headers will throw an error.
Multiple File Attachments
We support multiple file attachments on the contact form. We process them together and send them to you.
<formaction="https://api.web3forms.com/submit"enctype="multipart/form-data"method="POST"> ... <label> Your Resume </label> <inputtype="file"name="resume" /> <label> Your Photo </label> <inputtype="file"name="photo" /> ... </form>
Advanced File Uploader
Our Default HTML5 File uploader works only for single files up to 5 MB only. To upload multiple files or larger attachments, we recommend using our Advanced File Uploader. Please see the guide here