Huge Outlook OST file

If you are thinking why Outlook OST file is growing bigger and bigger every day regardless of how many emails you delete.
It seems like no matter how much you try to keep your inbox clean the free space in your hard disk is not getting bigger but only smaller and smaller every day.
Thankfully there is solution to reduce the size of this monstrous file!
Outlook provides an option to compress the OST file and reduce its size. Here is how:

Open file > Account setting > Account settings…

Select Data Files tab and click on Settings…

In the new window, select Advanced tab and click on Outlook Data File Settings…

Finally click on Compact Now button to start compacting process.

Depends on the file size this process could take long time so make sure you do this process when you are not expecting to send or receive any important email because during this process you are not able to use Outlook!