Your confidentiality is assured - we are professional:

We treat your file(s) with care
We keep your material secure and it remains confidential
We keep file(s) virus-free (we will advise if yours were infected)
We will not reveal or provide your contact details to anyone else

We are technical:

We look at problems/processes rather than content
We work efficiently – there is no time for reading/comprehending content
We have kept security functional yet reasonable. To access your file(s) you need to know the unique submission code, your unique password, and you must also pay for the solution!

We exchange information with you purely for the purpose of once-off technical help, therefore:

We only contact you to advise regarding progress on your submitted problem
We will not contact you for any reason in the future once your problem has been reviewed and/or fixed

If you are still concerned about the security of your materials simply edit out the parts which you consider sensitive.