In this scenario, you can either split the PST file or compress PST file. You can achieve this either by creating a new PST file and moving some data to it or compressing PST by reducing the size of attachments in a PST file. Another approach to reducing the size of PSTs is to use software that does that for you. A PST Splitter tool splits PST files by size, folder, date, etc. It is a better solution as it is less time-consuming and more efficient than manual methods.

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A large Outlook PST (Personal Storage Table) file size can cause performance issues and may lead to problems with email storage and management. Here are some tips on how to deal with a large Outlook PST file size:

Archive old emails: Move old emails that you don't need to access frequently to an archive folder or a separate PST file. This can help reduce the size of your main PST file and improve Outlook's performance.

Delete unnecessary items: Go through your mailbox and delete any unnecessary items such as old emails, attachments, and items in the Deleted Items folder. Empty the Deleted Items folder to permanently remove them from your PST file.

Use the Compact feature: Outlook has a built-in Compact feature that can help you reduce the size of your PST file by removing any empty or unused space. To use this feature, go to File > Options > Advanced > AutoArchive Settings, and click on the "AutoArchive" button. You can set up automatic archiving of old items and specify the frequency of the archiving process.

Split your PST file: If your PST file is still too large, you can consider splitting it into smaller PST files. This can be done using the Outlook Import/Export wizard. Go to File > Options > Advanced > Export, and select "Export to a file." Follow the prompts to create a new PST file and transfer some of your emails to the new file.

Use mailbox cleanup tools: Outlook has built-in mailbox cleanup tools that can help you identify and delete large items, such as emails with large attachments. You can access these tools by right-clicking on your mailbox folder, selecting "Properties," and clicking on the "Folder Size" button.

Consider using an online email storage service: If you frequently receive large attachments or have a lot of emails with large file attachments, you might consider using an online email storage service, such as OneDrive, Dropbox, or Google Drive, to store your attachments instead of keeping them in your PST file. This can help reduce the size of your PST file and free up space on your computer.

Regularly back up your PST file: It's important to regularly back up your PST file in case of any data loss or corruption. By having a backup, you can restore your Outlook data to a previous state and potentially reduce the size of your PST file in the process.

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Peter