What to Do When Outlook Storage File is Full

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Solution 1: Delete Old Emails

The simplest solution is to clean up your mailbox by deleting unnecessary emails.

1. Sort emails by size (File > Properties > Folder Size)
2. Delete large email threads you no longer need
3. Remove emails with large attachments
4. Empty the Deleted Items folder regularly
5. Use Outlook's Cleanup tool (Folder > Cleanup)

Solution 2: Compress PST File

Outlook has a built-in compression feature that can reduce PST file size.

1. Go to File > Info > Account Settings
2. Select Account Settings > Data Files
3. Select your PST file and click Settings
4. Click "Compact Now" button
5. Wait for compression to complete

Solution 3: Archive Old Emails

Move older emails to a separate archive file to keep your main PST smaller.

1. Go to File > Tools > Mail Cleanup
2. Click "Archive..."
3. Select folders to archive by date
4. Choose a location for the archive file
5. Set date cutoff (e.g., emails older than 1 year)

Solution 4: Switch to IMAP

Cloud-based email storage removes the PST limit entirely.

• Emails stored on server, not local computer
• No size limits (managed by provider)
• Access from multiple devices
• Automatic backup and sync
• Our recommended solution!

Solution 5: Create Multiple PST Files

Split your emails into multiple PST files to stay under limits.

1. Create new data file (File > New > Outlook Data File)
2. Move folders to the new PST
3. Organize by year or category
4. Close unused PST files to improve performance

• Regularly empty Deleted Items folder
• Avoid downloading attachments locally
• Use cloud storage for large files
• Set up auto-archive policies
• Consider IMAP for new accounts
• Monitor mailbox size monthly