WP user front end pro – file uploads – attachments

I installed wp user frontend pro, my problem is when i added file upload custom field to my form, it is showing only limited image file types like jpg, jpeg, png etc. Its not allowing to upload a image file of TIFF type from front end — it is showing front end error — how to include the extension of TIFF file type or how to allow all type of images to upload….

please can any fix this issue