If your e-mail button looks like this..

.. then you may not have the right permissions given by your Qbil-Trade administrator.

A Qbil-Trade administrator can set the ‘Delete’ permission for ‘Mutations, email contracts’ in the user permission screen. Please request this at your Qbil-Trade admin.

If you do have this permission, but still cannot send the e-mail because the button remains greyed out, it may be because the contract has not been authorized for e-mail yet. E-mail authorization is an optional configuration option in Qbil-Trade. Please make sure this checkbox is checked:

This only applies to the contract and sales invoice screen. Other documents do not have an authorization check available.