The following will guide you through the procedure of running a fast sync via geth --fast on Windows OS 10 for Mist for those running their Ethereum Wallet client for the first time.

Note:--fast can only be run if you are syncing your blockchain from scratch and only the first time you download the blockchain for security reasons.

Step 1: Open command prompt (Administrative privileges not required): 

Step 2: Go the file directory for geth which looks like following on Windows OS: ~\Ethereum-Wallet-win64-0-7-4\resources\node\geth

and drag using your mouse the geth file (a) from its location and place it into the command prompt window (b):

Step 3: You would see the following below if you did it properly: path to the geth file in your command prompt window

edit geth.exe to geth --fast as seen in (a) below.

Step 4:Click Enter and you should observe the following below if successful as the node begins to download the blockchain data; 

You can allow it to run till it has download the lastest block in the blockchain, point at which you would see ethereum start-up splash page below progress bar become completely filled up.

Step 5: Once all the blocks have been successfully downloaded you can close your command prompt window.

Error:

1. Network Time error: if you see the following as shown in the picture below while geth is running: 
   
   Solution: 

• • Right click time (a) at the bottom right of the your screen as shown in picture below: 
    
  • Select Adjust date/time and click Additional date, time & regional settings (a) in picture below located near the bottom right of your page.
     
  • Click set date and time(a) as shown in picture below:
    
    
    
    
  • Click Internet Time (a) and Change settings (b):
    
    
    
    
  • Click synchronize with internet server time(a), select time.windows.com as your server, click update(b) and press OK.(c)
    
    
    
    This should fix network time error.