Review the handout for how to use 7 Zip.
7zip encryption guide V1.2.docx (sharepoint.com)
Only send encrypted documents to clients if it is essential and ensure you advise the client will need to download 7 Zip software to open the encrypted file once received
Always send the password in a separate email to the encrypted document. • Only encrypt information which is sensitive e.g. – contains the clients creditor account numbers or contains the budget, if you are unsure please check with your Team Leader.