Sharing a whole drive in Windows 7 on a network without a password can be convenient in certain scenarios but can also pose security risks if not done correctly. Here's a step-by-step guide on how to do it:

1. Open 'Computer' or 'This PC' on your Windows 7 machine.
2. Right-click on the drive you want to share and select 'Properties'.
3. Go to the 'Sharing' tab and click on 'Advanced Sharing'.
4. Check the box that says 'Share this folder'.
5. Click on 'Permissions' and set the permissions to 'Everyone' with 'Full Control'.
6. Click 'OK' to apply the changes.
7. Go back to the 'Sharing' tab and click on 'Share...'
8. In the 'Network Path' field, type a share name for the drive.
9. Click 'OK' to close the sharing settings.
10. Now, the drive should be shared on the network without requiring a password.

It's important to note that sharing a drive without a password can expose your data to anyone on the network, so make sure to only do this on a trusted network or consider setting up password protection to enhance security.