What Happen When tour OST file become too large

OST to PST Converter /June 12, 2025

An OST file stores offline copy of essential outlook data ,including email, contact, and attachment .Day by day message add in OST file and OST file size increase .If OST file not manage properly then OST file cross size limit and it effect outlook performance or even Application crash .In this blog we explore what happen When OST file become tool large and provide method to resolve these issue

Top Reason why your OST file Become too large in Outlook

There are several reason for OST file increase in size.

  • Sending receiving numbers of email daily basis
  • Storing email with heavy attachment (such as image ,video ,or document)
  • Regularly not delete or archive old email and along with not empty Deleted Item folder
  • If Outlook configure a large amount of email for offline

All these factor contribute to increase OST file size

What happen when your OST file become too large

Oversize OST file generate various problem

  • Outlook unbale to open or load oversize OST file
  • Once OST file cross it size limit then no new add data with OST file
  • An oversized OST file disrupt many Outlook functioning
  • Large OST file easily corrupted

What is maximum size limit for OST file?

OST file size depend on version of Microsoft Outlook

  • Outlook 2007 Support OST file Up to 20 GB
  • Outlook 2010 and later Support OST file Up to 50 GB

Once file size reach its size limit ,immediate manage and reduce file size

How to Manually fix OST file too large issue in Outlook

There are several manual method available to resolve issue in oversize OST file. applying these method for reduce risk of file corruption

  • Regularly remove outdated email from OST file
  • Download important attachment on your device and delete them from outlook.
  • Permanently delete item from “Deleted items folder” to free up space in OST file
  • Rename exist OST file and allow outlook regenerate a new OST file

Disable or Remove Unwanted add-ins in Outlook

When OST file Become too large ,it is important reduce size OST file to improve Outlook performance here is many method for reduce size of OST file

  • Once Outlook open ,follow these steps
  • click on file tab in top menu
  • Select option from sidebar
  • choose add-in from left hand menu
  • Next select COM add-ins from dropdown list and click Go
  • Uncheck all add-ins that not use and click OK

Use Outlook Built -in too to Compact large OST files

Reduce size of OST file by removing all unnecessary data. follow these step

  • First ,Navigate home tab in Outlook and open Deleted items folder
  • Right click on folder and select Empty folder for permanently delete it.
  • Next follow these step for compact
  • Click on Data file tabs ,then choose OST file and click settings
  • Next navigate Advanced tab and click Outlook Data file Settings
  • Finally click compact Now reduce OST file size

How to turn off shared folder Sync in Outlook

Shared folders in Outlook increase size of OST file size ,which effect Outlook performance Disable synchronization for shared folders by following these simple step:

  • Open Outlook and click on file tab
  • Next navigate Account Setting then select Account setting from dropdown menu
  • Under Data file tab ,select OST file file associate with account
  • Click setting then navigate advance tab
  • Next select Outlook Data File Settings and uncheck option Download Shared Folders.
  • Finally click OK ,then close and restart outlook application to apply changes

Disadvantages of Using Manual Method

Manual method resolve minor issue with Outlook OST file they have many limitation .Below give many draw back of Manual method

  • Manual method involve multiple steps and which take long time for complete it
  • If OST file highly corrupted ,manual method fail resolve it.
  • Risk of accidental data loss when use manual method

Top recommended tool to repair and Manage OST file too Large

Goldytools OST to PST Recovery is an effective solution for recovering corrupted OST file .It allow you spilt OST file into multiple smaller size of PST file which you size define in tool without data lose or technical complexity .Company provide demo version that include all feature and you save 25 items per folder .if you satisfied with demo version ,you purchase full software

Conclusion

Above we share multiple method to reduce size OST file .you are use either manual method and professional method for get data from corrupted OST file .we recommend using professional tool

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