Granting Permission To Network Drive

Question

I am in need of giving a new user access to a network share. Not the entire share, only one folder in the share. I have clicked the folder in the share, I want this user to have access to, and given full permissions, however anytime the user tries to access the share they get an error message of

Windows can not access
\\servername\shares\mainshare\department\spreadsheets

Check the spelling of the name.  otherwise, there might be a problem with
your network.  To try to identify and resolve network problems 
click Diagnose

EDIT
It is a windows 7 machine attempting to connect to a share on a Windows Server 2008 machine.

EDIT # 2
I have attempted multiple times of right clicking the folder, choosing the security tab, clicking advanced and setting the user settings like below:

Type = Allow
Name = username
Permission = Full COntrol
Inherited From = not inherited
Apply To = this folder, subfolders and files

However, this still produces the error message.

Answer 1

Reviewing a Windows 7 machine (as I recall, Win 2008 ought to be rather similar...)

Access the ("right click") context menu for the desired ("spreadsheets") folder.

You've already expressed going to the Security tab. Good. Now, go to the Sharing tab.

Choose "A_d_vanced Sharing...". Check choose the "_P_ermissions" button.

Check things out graphically: Go to Control Panel, Administrative Tools, Computer Management, (your computer name), Shared Folders, Shares.

Get to a command prompt that has User Account Control elevated, and run: net share Spreadsheets
(or whatever the name of the share is).

If you have further challenge, copy the output and paste it into this SuperUser.com question.