How to access your Windows shares from your Raspberry PI?

• on your Raspberry PI create a folder for the share, for instance if you want to share your (shared) Windows dropbox folder:
  mkdir /home/pi/dropbox
  
• mount the dropbox share on the new folder:
  sudo mount -t cifs -o username=windowsusername, password=windowspassword //192.168.1.xxx/dropbox /home/pi/dropbox

If you want to mount that share automatically on boot, add the following line to the file /etc/fstab

• open the file for editing:
  sudo nano /etc/fstab
• add the following line:
  //192.168.1.xxx/dropbox /home/pi/dropbox cifs user=windowsusername,pass=windowspassword,_netdev 0,0

windowsusername: username for the windows machine
windowspassword: password for the windows machine
192.168.1.xxx: IP-address of the windows machine
192.168.1.xxx/dropbox: IP-address plus the name of the share on the Windows server

Good luck!