How to Configure OST File Size Limit in Outlook?

Every OST file has definite file size that maintains the saving space in Exchange Server and also in user’s system. For better system and Exchange Server functionality, it is always advised to set the OST file size maximum to 1 GB. Beyond 1 GB the system performance gets affected i.e. speed may get slow, low response time and some more ill effects.

Usually, when mailbox reaches 2 GB limit, it stops saving the mails. Consequently, user cannot save the upcoming mails and it leads to technical mess. For any user with some technical guidance it is very easy to make the way for limiting the OST file size. There are two ways to limit the OST file size without affecting the file content.

WarnFileSize Registry Entry: The registry determines the allowed file size which can be saved to some extent. Once the saving saturation capacity is reached, no more files could be saved either from OST or PST. However, user can increase the physical file size as it is completely independent domain.

MaxFileSize Registry Entry: This registry limits the maximum file size of OST files to be saved and maximum file size to be saved. When maximum saving limit is reached, the Outlook stops saving the OST files.

In some cases it is observed that registry values do not exist and it is user’s responsibility to create according to the Outlook version.

How to create Outlook Registry?

To create the registry values, it is advised to follow these steps:

  1. Click ‘Start’ button followed by clicking ‘Run’. In command line, type Regedit and expand these registry keys:
    • For Outlook 2003
      HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\11.0\Outlook
    • For Outlook 2007
      HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook
    • For Outlook 2010
      HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\14.0\Outlook
    • For Outlook 2013
      HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\Outlook
  2. Hit Edit menu and select ‘New’ then click ‘Key’.
  3. Type OST file name which is to be limited.
  4. Now click DWORD value.
  5. Write MaxFileSize and hit Enter key twice.
  6. In Edit DWORD value Window, enter the required value and click OK.
  7. Create another DWORD Value WarnFileSize and repeat the above steps.
  8. Now, close the registry.

Once the Outlook registry is created everything is in user’s control. However, close attention has to be paid while making changes in the registry values. This is because during making the changes in registry values through manual process, there is possibility of deletion of some important files. Therefore, it is recommended to take back-up of the registry values before making any changes.

For new users who do not have any knowledge of making registry changes, it is advisable to take assistance of professional. Once OST file size limit is configured in registry values, the Outlook activates the compact function so that unutilized space can be utilized for saving the OST files. In case the process seems complicated user can go ahead with OST to PST Converter Tool. It not only manages the time but also sort outs every OST-related queries. Just download the trial version of the tool to know more about it. Upon satisfaction user can purchase the licensed version.