For many the old zip and password will be fine. For others I'd read http://www.howtogeek.com/203708/3-alternatives-to-the-now-defunct-truecrypt-for-your-encryption-needs/
But remember all these are subject to an occasional loss. That is, you read folk that did not have backup copies and the encrypted folder was damaged and they lost it all.
Are you aware of the backup need? Many aren't.
What is the best software to encrypt folder on windows?
Because I work on a company how has sensitive documents on the computer and we would like to secure them.
Thank you in advance for your help.