Quick overview:
How to: Merge two PST files and fix the Outlook file size error
Guest author: Tony Landry
Microsoft Outlook has been one of the most popular email clients for decades and has been used primarily for sending and receiving emails ever since. However, with excessive use and thousands of emails, it can happen that space on the hard disk becomes scarce. To get around this problem,
However, problems can sometimes occur during recovery: Fortunately, there are professional data recovery tools such as Remo Data Recovery Tool, which can be used to recover data without any problems.
This works not only with data on your hard disk but also with defective or damaged PST files. Since the complete functionality depends on Outlook, you can also directly use the Remo Outlook PST Repair tool and fix any errors.
Even if you have a functional PST file, you may still receive error messages about invalid file sizes in Outlook. However, the problem often occurs with versions older than Outlook 2002. Even if versions 2007, 2013, 2016 and 2019 do not have a file size limit, we recommend that you do not exceed 20 GB - otherwise there is a risk of a data crash.
Many users archive or create PST files to back up and restore their emails. Unfortunately, this also means that your Outlook data is scattered all over the place in the form of PST files. To avoid these problems, you should merge your Outlook PST files back together. This is how it works:
Create a new Outlook file
- Open Outlook and click New item at the top. Then click on More items and here on Outlook data file.
- Give it a name of your choice and click OK.
- You will now see the newly created Outlook data file on the left-hand side.
Combine PST files into a new file
- Open Outlook and click on File or Start.
- On the left-hand side, select Open and export - and then Import/Export.
- In the wizard, now select Import from another program or file.
- Now select Outlook data file (.pst) and click Next.
- Now click on the Browse button and select the PST file you want to merge. Then continue with Next.
- Click Done now
If you have carefully followed the steps above, the PST file will be merged with the new file and contents. You can now use it without having to worry about file sizes.
Conclusion
As usage increases, Microsoft keeps its programs up to date to meet user requirements. So if you are using an older version of Outlook, you should switch to the new one. This will not only give you advantages in terms of new functions, but you can also avoid errors.
So if you want to use an old PST file, the steps above will help you to merge this data. This will make them work properly again.
Written by: Tony Landry
Tony is a Microsoft Support Specialist who can fix stubborn Outlook and Windows errors. Loves optimizing and expanding his horizons as well as creating email content.
support specialist, experienced in tackling beasty Outlook and Windows OS errors. Enjoys tweaking and exploring new horizons to develop content for email.

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