What is the Difference Between MAILBOX SIZE & OST FILE SIZE

What is the Difference Between MAILBOX SIZE & OST FILE SIZE

Internet is full of queries when it comes to finding out the difference between mailbox size and OST file size. Do you know why? Users who like to use MS Outlook 2000 and 2003 face the problem. It causes data corruption if the file size goes beyond its limit. Many MS Outlook users share the problem with tech forum websites in order to seek help. Let’s understand the matter with a query.

"We are a small group of the organization. We use MS Outlook 2003 version to operate our database. Everything is fine with the MS Outlook version. We don’t find the necessity to move to the latest 2016 version. However, we have one problem and it is the difference between MS Outlook file size and the Mailbox size in Exchange Server. Is there any solution to fix the problem? There is a huge difference between the file size of OST and Mailbox size."

The problem cannot be ignored considering it a small problem. A large OST file can become inaccessible because it increases the chance of data corruption. You can archive OST items or can compress the OST file size

The problem is usually faced by users using older versions of MS Outlook. Users using the latest versions like 2013 and 2016, 2019, 2021 are not facing such an issue because Microsoft has tried to fix the problem. Do you know MS Outlook 2013 or2016, 2019, 2021 save the OST file to around 30% smaller than the mailbox file size? It is because Outlook's latest versions reduce many streams of text. It can be like zipping a large text tile. It is why users get smaller OST files.

The file size of OST and Exchange Server mailbox can vary even after disabling all extra caching and emptying “The Computer Only” folders. For Outlook 2010 and below versions, it is normal that the OST file size is 20-30% more than the mailbox size. It shows store storage incapability of OST files. It is also the way Exchange measures the size of the mailbox. Exchange 2013 is an upgraded version that calculates data precisely.

It is not easy to compress an OST file size. It may cause data loss. For 2003 to 2010 users, a large OST file can be a problem if the size goes beyond imagination. Users can compress an OST file manually or can consider a third-party utility. Below are some measures to reduce OST file size.

Reducing the OST File Size

If the mailbox stores items in the single mailbox or the mailbox size is larger and Outlook freezes or is not responding.

  1. Recreate OST File: One of the best solutions to get rid of the file size issue with OST is to recreate an OST file. Instead of looking for a compressing app, you can recreate an OST file. For this, rename the existing file with . old and exist from Outlook. As you rename it, Outlook will re cache mailbox in a new OST file as you restart MS Outlook. To recreate or recovery OST try Spikevare OST Recovery tool.
  2. Sync Filters: Another smart solution is synchronization. Users can calculate what can be saved in OST and what can be synchronized if the size of folders is large. Users can set the Synchronization Filters.
  3. Sync Slider: Take the help of Sync Slider to cache recent items instead of caching the entire mailbox in Outlook 2013 and 2016 versions.
  4. Disable Shared Folder's Caching: There are some shared folders that we don’t need often. So, it is better to disable the function to cache shared folders.
  5. Disable Public Folder's Favorites Caching: Like disabling shared folder’s caching, you can disable public folders catching. Public folders are excellent to collect, share, and organize information about particular topics in an organization.
  6. Delete Some Public Folder's Favorites: MS Outlook can cache copies of emails locally. If you think that some topics from your public folders are not necessary to keep, you can delete them rather than disabling the public folders entirely.
  7. Duplicate Gmail: It is an additional feature offered to PST file format users where users integrate with Gmail for storing emails. Duplicate storage can be avoided.

Conclusion

The size difference between MS Outlook 2003-2010 Exchange Mailbox and OST cannot be solved easily. If you want to save time and effort, you can use an Spikevare OST to PST Converter tool. It is one of the best solutions. Another thing you can do is to switch to the latest Outlook 2013 and other latest versions of the OS. These are a few things that can be helpful in managing OST file size.

Spikvare OST to PST Converter


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