To store a variety of data, including emails, contacts, calendars, notes, and journals, Outlook creates PST files. PST files come in two flavours: ANSI and UNICODE. Outlook 97 and 2002 ANSI PST files are limited to 2 GB, however, Outlook 2003 and 2007 enable up to 20 GB.
Outlook versions 2021 and later offer up to 50 GB of storage and can produce UNICODE PST files starting in 2003.
Overdoing it can lead to Outlook problems including inaccessibility, sluggish performance, Outlook crashing, and inability to send and receive emails, as well as PST corruption. Increasing the size of the PST file using the techniques described in this thorough article for Outlook 2021, 2019, and previous versions is essential for PST file recovery.
What are the Causes?
When the Outlook Personal Folders (PST) file, which holds contacts, emails, and other data, exceeds its size limit—typically 20 GB for Outlook 2007 and later versions—the error “Outlook PST file has reached its maximum size” frequently appears. A lot of emails, attachments, and calendar entries might be the cause of file enlargement.
Its bloating is also caused by inadequate maintenance, such as not routinely compressing or archiving the PST file. The issue may get worse due to outside influences like synchronization problems. To stop recurrence, proactive file management and organization are crucial in addressing these issues.
How does it affect the Users?
Users are greatly impacted when Outlook PST file sizes are exceeded. Users experience problems including inaccessibility, sluggish performance, and unresponsiveness in Outlook when PST files surpass a certain size. The restrictions may make it difficult for email correspondence to operate normally, making it impossible to send and receive messages. PST file corruption can cause irreversible data loss, impacting calendars, contacts, emails, and other important data.
Methods to resolve the error
Method 1: Empty PST File to Create More Space
To free up space in your PST file for new emails, you have two options: emptying the Deleted Items folder or archiving older or large emails to a local PST file and then removing them from your default PST file. Follow these steps:
To clear the Deleted Items Folder:
- For Outlook 2013, 2016, or 2019, go to File > Info, then click Cleanup Tools > Empty Deleted Items Folder.
- Confirm by clicking Yes when prompted.
- This action will eliminate all deleted emails and mail items from your Outlook PST file.
For Outlook 2010 and 2007, right-click on the Deleted Items folder and select Empty Folder to erase deleted mail items and empty the PST files.
To archive old emails and create free space in your Outlook PST file:
- In Outlook 2013, 2016, or 2019, navigate to File > Info and click Tools > Clean Up Old Items… or Cleanup Tools > Archive.
- For Outlook 2010, click File > Cleanup Tools > Archive.
- In Outlook 2007, click File > Archive.
- Choose the folders to archive emails from and set the date using Archive items older than.
- Click Browse to specify a location for saving the archived emails.
- This process will archive all emails older than the specified date into a local PST file at your chosen location. Open this local PST file in Outlook to access archived mail items.
- Delete the archived emails older than the selected date from the default PST file to create space and resolve the “PST has reached its maximum size” error.
Method 2: Increase PST File Size Via Registry Editor
You can modify or set limits on the PST file size by creating or modifying the MaxFileSize, WarnFileSize, MaxLargeFileSize, and WarnLargeFileSize registry entries on your Windows PC. To adjust the PST file size limit, follow these instructions:
- Press Windows+R, type regedit.exe, and press ‘Enter’ or click ‘OK.’
- Navigate to the registry entry by following the provided path and then select PST.
- If the MaxFileSize, WarnFileSize, MaxLargeFileSize, and WarnLargeFileSize registry entries are absent, create them. Right-click on an empty space, and choose DWORD (32-bit) value.
- Name the registry entry MaxFileSize and double-click on it.
- In the Value data field, enter a value in bytes (e.g., 1GB = 1024*1024*1024 bytes).
- Click ‘OK.’
- Repeat these steps to create and set values for WarnFileSize, MaxLargeFileSize, and WarnLargeFileSize.
By following these steps, you can raise the PST file size limit, providing more storage space for mail items and resolving the “Outlook.pst has reached its maximum size” error.
Method 3: Outlook PST File has Reached its Maximum Size Not Resolved
To address the “PST file has reached the maximum size” error, the optimal and final solution is to repair the corrupt PST file using the ScanPST.exe. If the ScanPST.exe tool crashes or remains unresponsive for an extended period, it may indicate severe damage or corruption within the PST file. In these instances, automated tools such as Stella Repair for Outlook might prove ineffective in resolving the corruption due to its inherent limitations.
Following are the steps to resolve this error by using Stellar Repair for Outlook:
- Launch the Software and Select the PST File: Open Stellar Repair for Outlook and select the option to repair Split the oversized PST file that has reached its maximum size.
- Scan the PST File: Follow the software’s prompts to thoroughly scan the corrupted PST file. This process involves analyzing the file for errors, corruption, or issues contributing to its maximum size and giving the preview of PST mailbox items to verify.
- Save the Repaired PST File: Once the preview process is finished, the software will likely prompt you to save the repaired PST file in multiple saving options such as PST, MSG, EML, RTF, PDF, and HTML. Save it in a location of your choice, ensuring it is easily accessible.
So, these are some of the most effective methods that can help you fix the “Outlook PST file has reached its maximum size” error. Resolving this error is essential for enhancing the functionality of the Outlook application. In case PST files get corrupted due to their large size, the 3rd party PST Recovery tool could be the live savior to access the Outlook mailbox data. But I would like to suggest you keep the size of the PST file below the threshold size. Regularly archiving the old mailbox data or deleting unnecessary items are recommended ways to keep your PST file in a healthy state.