If you are using older versions of Microsoft Office, the same thing applies. Office 2010 reaches its end of life in January 2020 as well. While your Office applications (Word, Excel, PowerPoint, Outlook, and Access) will continue to run, they will no longer be updated, no longer be eligible for technical support, and put your business and your clients increasingly at risk the longer they are in use.
To keep your documents and your data safe, you will need to either install a newer version (such as Office 2013) on every computer in your organization, or move to the Office 365 platform across the board. Either way, it can be a Herculean undertaking, and one that you may not be equipped for.