Open outlook2010, click on the "File -> Information -" Account Settings 
select email account, and click on "Change" 
Cancel "Use Cached exchange mode" in front of hook 
click on "Other Settings" 
prompt next change will take effect after the restart outlook, click "OK" to 
select the "advanced" tab and click on the "outlook data file settings" 
click "disable offline" 
prompts unusable ost file, click "Yes" 
and click "OK" 
to close outlook software,
open "my computer"
input the address, and press Enter to open
% userprofile% \ Local Settings \ Application Data \ Microsoft \ Outlook \ 
Create a new folder on the D drive "mailbox files" (specifically to see the D drive the remaining capacity, if the D disk space is insufficient, you can in other spaces E, F, G, etc. enough disk)
selected ost file with the extension, a shear disk D to mailbox folders 
open Outlook2010, account settings
Select Advanced, outlook data file settings 
click "Browse" to select the D drive mailbox folder ost file 
can see the path has been changed to the D drive, and click OK 
to exchange cached mode on the hook, and the next step 
to take effect after the restart outlook2010