Simple Ways to Compress PST Files & Fix Slow Outlook Issues

Why Compact PST File? How It Grows Large?

If MS Outlook performance is sluggish, slow, or doesn’t open correctly, hangs in between, then undoubtedly, an oversized PST is the cause. If you repair oversized Outlook PST file, then it can help reduce the consumed storage space and improve Outlook performance as well. It is quite similar to clearing digital clutter more by archiving and not by deleting important data. 

Some common reasons why a PST file tends to expand are: 

• Years of emails and contacts stored altogether
• Data from multiple Outlook profiles is combined in one
• Numerous sent and received attachments accumulate 
• Deleted emails still remain in trash or junk folders and aren’t removed entirely 
• The Auto-Archival feature is disabled, which doesnt clears the space for new emails 

So, it is quite essential to compress them instead of deleting them to completely free the allocated space and prevent Outlook or file crashes, corruption, and other issues. 

Effective Ways to Compress PST Files & Fix Slow Outlook 

In this section of the blog, go through all the free and professional methods to compress and compact PSTs to improve performance. These are discussed in full detail here for easy understanding and quick implementation. 

Manually Compress Outlook PST Files

We are going with two different free methods for compacting PST files to a smaller size that is acceptable and doesn’t affect performance. 

Way 1: Compact PST with Built-in Feature 

1. Open Outlook and move to File and click Account Settings. 
2. Again, press Account Settings, and a dialog appears. 
3. Then, go to the Data Files tab and select your oversized PST. 
4. Further, click Settings from the options, and a dialog appears. 
5. Finally, press Compact Now to reduce the size of the file. 

Note: With this, only the unused white spaces are removed, and the emails aren’t deleted. It is best if your PST file size is moderate and you are maintaining them regularly. 

Way 2: Compress Outlook Data File by Archive

1. In the File → Info → Tools, click on Clean Up Old Items. 
2. It will open the Archive dialog where you can pick a date range. 
3. Then, select folders for archival and save them to a new PST. 
4. Alternatively, you can enable Auto-Archive or set an archive folder. 

Note: For long email histories, it is an efficient option without the actual deletion of emails. 

Automatically Compress PST Files 

When the PST files are extremely large in size, or Outlook is too unstable, then a professional solution is an optimal choice. SysInfo PST Compress and Compact Tool is a smart and dependable utility to reduce the PST size without Outlook installation. It ensures that the data fidelity is preserved, and you can even secure it with passwords. Additionally, the tool offers support for all ANSI and UNICODE PSTs for any Outlook version and works flawlessly on both Mac and Windows. Moreover, it enables batch compression and has a Demo Version for evaluation. 

Steps to Quick Compress Outlook Data File

1. Launch the PST Compress Tool and pick Single or Multiple Files and tap Next.

2. Then, press Select File/Select Folder and upload PST files to compact. Click Next.

3. Further, preview the data within the PST file, select folders from the tree, and click Next.

4. After that, choose how you want to compress the file and manage the resulting file.

5. Finally, select your destination path and click Start Compression to reduce the oversized PST.

That’s how straightforward this process is with the easy-to-use interface. It is particularly useful if your organization has multiple mailboxes, legacy archives, oversized PSTs, and requires bulk compression at once with data safety. 

Which Method is Best to Compact PST File?

From the distinction table below, you can identify which is the best way for PST compression: 

Conclusion

If your Outlook startup is low, the search function is lagging, you receive Outlook not responding issue, or the PST size has exceeded 10-20 GB. Then, it is quite important to compress PST files to avoid Outlook instability and resolve slow Outlook issues. With proper compression and compaction on a regular basis, you can ensure steady Outlook performance, reduced clutter, and free storage. The manual fixes may help to some extent, but for a scalable solution, get the automated software.

Frequently Asked Questions

About The Author:

Simran Bhatia

Simran Bhatia is a technical content writer engaged in writing clear, concise, and SEO-optimized content. With a background in computer science and a passion for writing, I thrive to deliver complex technical content in simple layman terms.