Make a File Read-Only

1. Choose Office Button => Save As. The Save As dialog box opens.
2. Optionally, select a file location from the Save-in dropdown list.
3. Enter a filename. Click the Tools button. A drop-down menu appears.
   
   
   
   
   
   
4. Choose General Options. The General Options dialog box appears.
   
   
   
   
   
   
5. Click the Read-Only Recommended option. Click ok and then click save.
   The Read-Only option is only a recommendation. Users can save changes to a read-only file by giving it a different name or saving it in a different folder.

Open a File as Read-Only or Copy

1. Choose Office Button => Open. The Open File dialog box appears.
2. Locate and select the file you want to open.
3. Click the arrow on the Open button. A list of options appears.
4. Choose Open Read-Only or Open as Copy. The file opens.
5. To save any changes to the file, you must choose Home => Save As and specify a different file name.
   If you open a file as a copy and do not use the Save As option, Excel uses the filename "Copy (#) filename" where # represents the copy number and filenameis the current filename.