Error Warning! on job applications

When applying for a job the candidate should download their CV in a PDF format! no problem, but I have tested this and applied for a job with a CV (in a different format) and this was excepted but did not show up at the other end (recruiter inbox). So as a ‘jobseeker’ I have applied but as a ‘recruiter’ I don’t have their CV. Can you put a (error notification into the theme) so when the jobseekers applies with the wrong formatted CV the system will inform them and not complete the application?