How to Fix Outlook Data File Too Large to Open Error? – Solved

Written By Andrew Jackson
Anuraag Singh
Approved By Anuraag Singh
Published On June 6th, 2024
Reading Time 7 Minutes Reading

Outlook data file too large to open” Are you encountering the same error? If so, get the solution here. In this article we will provide you a solution to fix the Outlook PST file too large to open with a complete step-by-step explanation. So if you are unable to access your large Outlook data file, read this article!

MS Outlook is the most used email client worldwide and stores all data information in PST file format. PST files have some size restrictions in the earlier version of Outlook. In Outlook 2000 and 2002, the maximum size limit was 2 GB. In Outlook 2003 and 2007, the limit is 20 GB and In Outlook 2010, 2013, and 2016, the limit is 50 GB+. As a result, Outlook performance drops in most cases, and users face Outlook data file too large to open issues. 

Here we have simplified this error in multiple ways. Do you want to know how? Let’s get started.

Note: PST file size issue can be fixed by compressing it. For this SysTools has developed PST compress tool. It allows users to delete the attachments and reduce mailbox size.

Reasons of Outlook Data File Too Large to Open Error

Nothing happens without a reason. If your Outlook shows error messages like “Outlook PST file too large to open” or error number – 0x00040820, then probably there is something wrong with your Outlook PST file. These errors can occur in the following circumstances:

  • Accumulation of emails, attachments, contacts, calendars, tasks, events, etc.
  • Large sized attachments in emails.
  • Use of plugins and add-ins.
  • Data in saved drafts, trash, sent items folders.
  • Duplicate emails, attachments, contacts, etc.
  • Files temporarily generated by Outlook.

How to Fix If Outlook PST File Too Large to Open?

MS Outlook does not offers any inbuilt features to break up large PST file to smaller files and easily open them. However, there are some indirect methods that help you to manage too large Outlook data file. Here are some possible manual methods to fix the problem Outlook data file too large to open.

Method 1. Open Large Outlook PST File by Moving Them

  1. Open Outlook >> File >> Account Setting >> Account Setting.
  2. Select the Data Files tab and click on Add button.
  3. Create or Open Outlook File” window will appear, name the file and select the location. Click OK button.
  4. Now, click on File >> Open >> Import.
  5. From the Import/Export wizard, choose the Export option and click on the Next button.
  6. Select the PST file and click Next.
  7. Choose the desired folder and its items to export. Check the Include Sub Folder option.
  8. Click on the Browse button and select the location to store the new file.
  9. Hit the Finish button.

Method 2. Fix Outlook Data File Too Large to Open Using Move To Folder

  1. Launch MS Outlook >> File >> New >> Outlook Data File.
  2. A new window will appear, here select the PST file and click OK.
  3. Give the required name for a new PST file in Create Microsoft Personal Folders window.
  4. Choose one or more folders to move in this new PST file.
  5. Click on Edit and select the Move to Folder option.
  6. Move Items window will appear, here, click on the New button.
  7. Type a name for this folder in Create New Folder window.
  8. In the “Select where to place the folder” option, click on the new PST file and click OK.
  9. Click OK to end the process to fix Outlook data file too large to open.

Method 3. Use Archive Feature Access Large Outlook Data File

  1. Open Microsoft Outlook >> File >> Archive.
  2. From Archive Window, select the “Archive this folder and subfolders” option.
  3. From the drop-down list, select the date for Archive items older than.
  4. In the end, click on the Browse button and select the desired location to save the archive .pst file. After clicking the OK button.

These three methods are not an appropriate way to overcome Outlook data file too large to open. It is a very long process and requires technical expertise to carry out the task.

Direct Solution to Fix Outlook Data File Too Large to Open Issue

To overcome all limitations and simplify this Outlook PST file too large to open, we recommend using the SysTools Split PST Tool, which is the best and most trusted solution. The application offers 4 options for breaking Outlook PST files like size, date, year, and folder. It has no limitations on file size, you can easily break large PST files according to your required size in MB / GB. The software supports ANSI and UNICODE PST files to separate oversized files.

Steps to Make Large Outlook Data File Smaller and Access Them

Step 1. Download, install and run the software on your computer if your Outlook data file too large to open.

download for windows    buy for Windows

Step 2. Add PST file, then click on Next button. Outlook data file too large to open

Step 3. Select Split by Size option to make the large Outlook data file smaller. Split By Size

Step 4. The tool display all split information so you can easily resolve the error “Outlook PST file too large to open”. Outlook PST file too large to open


If you want to Outlook data file too large to open then making them smaller is the best way to overcome without facing data corruption. Here, we discussed the manual and the professional solution that helps you to resolve Outlook PST file too large to open error. The manual solution has some limitations that’s why we highly recommend going with professional software. You Free Download the tool and test its efficiency.

Frequently Asked Questions

How Do I Reduce the size of my Outlook Mailbox?

You can try the Outlook Mailbox Cleanup tool which helps to delete unwanted data from Outlook data files. If it does not work, then you can use the tool provided by SysTools to resolve Outlook PST file too large to open. This software will help you to reduce the size of the Outlook mailbox.

How Can I Resolve Outlook data file too large to open Error?

This error message is displayed due to an oversized PST file. You can recover this error to decrease the size of large PST files. Use the tool to decrease the size of your Outlook data file and make them smaller.

How to Manage Large Outlook Data Files?

The best way to manage large Outlook data files is by making them smaller. To do you can use the manual as well as third-party tools. As there are many tools available in the market which are also helpful for splitting Outlook data.

How Do I delete Large Outlook Emails and Attachments?

You can also delete large emails to resolve issues of Outlook data file too large to open. Follow the steps to deleted emails:
1. Launch Outlook, click the Search folder from the folder list and then select New Search Folder.
2. Under Organizing Mail, select Large mail and click on the Choose from the Customize Search Folder.
3. In the “Show mail greater than” box, specify the size and click OK.


By Andrew Jackson

I am SQL DBA and SQL Server blogger too. I like to share about SQL Server and the problems related to it as well as their solution and also I do handle database related user queries, server or database maintenance, database management, etc. I love to share my knowledge with SQL Geeks.