DataVare Outlook PST Merge Expert Review: The Best Way to Combine Outlook Data Files

Introduction

Outlook has a tendency to accumulate PST files over time. A couple automatically generated files from Outlook's own settings, a backup from an old laptop, an archive from a former job all of a sudden you're juggling five different PST files with no easy way to discover anything.

A Windows desktop tool called DataVare Outlook PST Merge Expert was created especially to address this. The method preserves folder structure, email content, attachments, contacts, calendar entries and metadata while merging several PST files into a single, cohesive PST file.

What it combines between PST files:

· Emails with complete attachments, body text and headers

· Contacts and groups of contacts

· Schedule regular activities, meetings and appointments.

· Journal entries, notes and tasks

· Personalized folder names and a hierarchy of nested subfolders

Challenges

There is no built-in merging feature in Outlook. You can open many PST files at once and manually move items between them, but it is copying rather than merging. And when you have thousands of emails spread across dozens of folders, it quickly breaks down.

The issue becomes more challenging when:

· You have PST archives from several employers and have changed jobs.

· The PST archive of a departing team member needs to be combined with a shared mailbox.

· Over the years, Outlook generated auto-archived files that are currently dispersed across several drives.

· You want to import a single, clean PST instead of multiple broken ones because you're moving to a new computer.

· IT is combining user data following a merger or firm reorganization.

The information is available. Searching, compliance auditing or even just locating a certain email can be quite difficult due to its excessive prevalence.

Manual Methods

Before using any third-party software, I made a fair attempt to achieve this.

Method 1: Drag and Drop Between Open PST Files

Outlook lets you open several PST files at once. Theoretically, folders can be dragged into one another. It is effective for tiny volumes in practice. The procedure took more than a day, silently skipped items, and frequently halted for more than 20,000 emails spread across four PST files. There was no indication of what actually moved.

Method 2: Import/Export using Outlook's Built-in Tool

One PST can be imported into another using Outlook's Import feature (File → Open & Export → Import/Export). The issue is that, unless you explicitly intervene at each folder, it automatically flattens the folder structure, dumping everything into the target file's root a laborious and error-prone process at scale.

Method 3: Manual Copy using Windows File System

Combining PST files requires more than just transferring bytes. Since they are structured database files, it is impossible to merge them at the file system level without ruining both files.

Without considerable physical labor, none of these yielded a precise, clean output. I ended up using a specialized merge tool as a result.

Process for Merging PST Files Using Software

Step 1: Install and Launch

Installation took less than two minutes to complete. The UI launched without any solicitations for subscriptions or the need to create an account.

Step 2: Add PST Files

You can load the PST files you wish to merge using a straightforward "Add Files" button. I added four 800MB to 3.4GB PST files. Within roughly 20 seconds, all four loaded with folder previews.

Step 3: Examine the Structure

The program showed a complete expandable tree of each folder in each of the four PST files prior to combining anything. I could see the structure, item counts and folder names. This helped identify duplicate folder names in advance.

Step 4: Select Merge Choices

The utility provided two methods for merging:

· Combine all of the files into a single PST file.

· Emails from files with identical folder names are combined into a single folder in the output.

Since I wanted the Inbox and Sent Items folders in three of my PST files to be combined rather than duplicated, I selected the join-by-folder option.

Step 5: Set Output Location and Run

Click Merge after selecting a target folder on an external device. The operation took 52 minutes for four PST files totaling about 9.2GB and about 31,000 emails.

Step 6: Check in Outlook

Opened Outlook and imported the output PST. The folder arrangement was correct. Spot-checked emails from various original sources to make sure they were all there, formatted correctly, had openable attachments and had accurate timestamps.

Performance Insights

Overall Score: 4.7 out of 5

Strengths of the Tool

· Handles large PST: Manages big PST files without halting or crashing in the middle.

· Prevents duplicates: The folder join option avoids needless duplication of shared folders, such as Sent and Inbox.

· Preview choice: By previewing before merging, you can identify structural problems early on.

· Data preservation: Maintains all forms of data, including calendars, contacts, tasks and emails.

· No Outlook installation required: The merge can be performed without an active Outlook installation.

· Broad Outlook compatibility: The output is a normal PST file that works with any version of Outlook available today.

· Completely offline: No data is sent to other servers.

· No additional software needed: Clean installer with no third-party software included.

Known Limitations

· Window-based tool: No Mac version is compatible with this tool.

· Limited demo trials: There are item limits for the free version; a premium license is needed to fully combine huge PST files.

· No duplicate email detection: The same email may appear twice in the output if it is included in two source PST files due to the lack of automatic duplicate email detection.

· One Output File: the merge output cannot be divided among several destination PSTs.

· Speed depends on file size: Depending on the hardware, PST files larger than 20GB will take a long time.

· No command-line interface: The current version does not permit automation or scripting.

Buyers FAQs

1. Do the original source files get deleted or changed when PST files are combined?

No, a new merged output file is produced by the tool. During the procedure, your original PST files are read but not altered in any way. At their original positions, they are still intact.

2. What happens if the folders in two PST files have the same name?

Identically named folders are combined into a single folder in the output using the join-by-folder option. The conventional merge option preserves each source file's directories separately within the output structure if you would rather keep them apart.

3. Is the combined PST compatible with every Outlook version?

Outlook 2007, 2010, 2013, 2016, 2019, 2021 and Microsoft 365 are all compatible with the output PST. Outlook installations are compatible with both 32-bit and 64-bit versions.

4. Will all source PST files' contacts and calendar entries be included?

Indeed. Not only does the merging include email messages, but it also includes contacts, calendar appointments, tasks and notes. The output file contains all of the information from each source PST.

5. In a single process, how many PST files can be combined?

Multiple PST files can be combined in a single run with this program. Four files were processed concurrently without any problems during testing. Processing time rises in direct proportion to the total volume of data for very large numbers of files.

Final Thoughts

PST archives that are fragmented are a constant and slow source of annoyance. Over time, searching through four different files, keeping four different backups and manually keeping track of what's there add up.

Four PST files, nine gigabytes of data, 31,000 emails, and one output file with everything intact and well organized were all handled by the merge program with ease. In particular, the join-by-folder option prevented a lot of cleanup work that would have been necessary with a flat merge.

A real drawback is the lack of duplication detection; if the same email appears in several source files, you will have to manually clean those out afterwards. Depending on how your source PST files were made, that is something to consider.

It operates precisely and without technological complication for the primary task of merging disparate Outlook archives into a single usable file.

Ideal for: Anyone inheriting multiple PST files from a prior system; IT teams managing user data migrations; compliance teams needing unified email records; and individuals consolidating personal Outlook archives.

Less suitable for: Those who need command-line automation for large-scale deployments, Mac users or anyone who needs automatic duplicate removal.